diff --git a/.changeset/26112-26142-block-inline-title-translations.md b/.changeset/26112-26142-block-inline-title-translations.md
new file mode 100644
index 00000000000..6ec3859b152
--- /dev/null
+++ b/.changeset/26112-26142-block-inline-title-translations.md
@@ -0,0 +1,18 @@
+---
+'@objectstack/spec': minor
+'@objectstack/cli': minor
+---
+
+feat(spec): a joined report's block headings and a master-detail field's inline grid heading are translatable
+
+Clause-②: yes
+Metadata-protocol: added
+
+Two authored, user-visible labels had no translation slot, so a zh-CN user read them in the authoring language and `os i18n check` could not see the gap:
+
+- **A joined report's blocks.** The `reports` translation group declares `blocks`, keyed by the block's `name`: `reports.<report>.blocks.<block>.label` / `.description`. `translateReport` overlays them on each block of the served report (`GET /meta/report`), which is what the joined renderer draws above each block.
+- **A field's `inlineTitle`.** `FieldTranslationSchema` declares `inlineTitle`: `objects.<child>.fields.<field>.inlineTitle`, on the child object whose master-detail (or lookup) field declares the heading. `translateObject` overlays it on the served child object (`GET /meta/object`), which is what the console copies onto the parent's form as the inline grid's heading.
+
+Both follow the packaged-base rule (ADR-0029 D9.2a): a string an org re-authored on top of the packaged declaration keeps its text. An authored `inlineTitle` with no entry keeps its authored text; the child object's plural label is never substituted for it.
+
+`os i18n extract` scaffolds both keys and `os i18n check` counts them: a block's `label` / `description` under the report bucket, `inlineTitle` under the field bucket. A block without a `label`, or a field without an `inlineTitle`, is recorded without being demanded.
diff --git a/content/docs/references/api/protocol.mdx b/content/docs/references/api/protocol.mdx
index 551a6319339..fd5d355ab29 100644
--- a/content/docs/references/api/protocol.mdx
+++ b/content/docs/references/api/protocol.mdx
@@ -1778,7 +1778,7 @@ The published metadata item body, opaque by ruling (1C). Shape is the item's own
 | **globalActions** | `Record<string, { label?: string; description?: string; confirmText?: string; successMessage?: string; … }>` | optional | Global action translations keyed by action name |
 | **dashboards** | `Record<string, { label?: string; description?: string; actions?: Record<string, object>; widgets?: Record<string, object>; … }>` | optional | Dashboard translations keyed by dashboard name |
 | **datasets** | `Record<string, { label?: string; description?: string; dimensions?: Record<string, object>; measures?: Record<string, object> }>` | optional | Analytics dataset translations keyed by dataset name |
-| **reports** | `Record<string, { label?: string; description?: string }>` | optional | Report translations keyed by report name |
+| **reports** | `Record<string, { label?: string; description?: string; blocks?: Record<string, object> }>` | optional | Report translations keyed by report name |
 | **pages** | `Record<string, { label?: string; description?: string; title?: string; subtitle?: string; … }>` | optional | Page translations keyed by page name |
 | **flows** | `Record<string, { label?: string; successMessage?: string; errorMessage?: string; screens?: Record<string, object>; … }>` | optional | Screen-flow translations keyed by flow name |
 | **positions** | `Record<string, { label?: string; description?: string }>` | optional | Position translations keyed by position name |
diff --git a/content/docs/references/system/translation.mdx b/content/docs/references/system/translation.mdx
index d16708d3bf6..a28db115d72 100644
--- a/content/docs/references/system/translation.mdx
+++ b/content/docs/references/system/translation.mdx
@@ -66,6 +66,7 @@ Translation data for a single field
 | **help** | `string` | optional | Translated help text |
 | **placeholder** | `string` | optional | Translated placeholder text for form inputs |
 | **options** | `Record<string, string>` | optional | Option value to translated label map |
+| **inlineTitle** | `string` | optional | Translated inline master-detail grid title — overlays the field's own `inlineTitle` |
 
 
 ---
@@ -90,7 +91,7 @@ Translation data for a single object
 | **label** | `string` | optional | Translated singular label |
 | **pluralLabel** | `string` | optional | Translated plural label |
 | **description** | `string` | optional | Translated object description |
-| **fields** | `Record<string, { label?: string; help?: string; placeholder?: string; options?: Record<string, string> }>` | optional | Field-level translations |
+| **fields** | `Record<string, { label?: string; help?: string; placeholder?: string; options?: Record<string, string>; … }>` | optional | Field-level translations |
 | **_views** | `Record<string, { label?: string; description?: string; title?: string; emptyState?: object; … }>` | optional | View translations keyed by view name |
 | **_actions** | `Record<string, { label?: string; description?: string; confirmText?: string; successMessage?: string; … }>` | optional | Action translations keyed by action name |
 | **_sections** | `Record<string, { label?: string; description?: string; fields?: Record<string, object> }>` | optional | Section translations keyed by section name |
@@ -107,6 +108,7 @@ Translation data for a single field
 | **help** | `string` | optional | Translated help text |
 | **placeholder** | `string` | optional | Translated placeholder text for form inputs |
 | **options** | `Record<string, string>` | optional | Option value to translated label map |
+| **inlineTitle** | `string` | optional | Translated inline master-detail grid title — overlays the field's own `inlineTitle` |
 
 ### Nested Shape: `ObjectTranslationData._views[string]`
 
@@ -177,7 +179,7 @@ Platform translation data — the per-app groups plus the platform-only `setting
 | **globalActions** | `Record<string, { label?: string; description?: string; confirmText?: string; successMessage?: string; … }>` | optional | Global action translations keyed by action name |
 | **dashboards** | `Record<string, { label?: string; description?: string; actions?: Record<string, object>; widgets?: Record<string, object>; … }>` | optional | Dashboard translations keyed by dashboard name |
 | **datasets** | `Record<string, { label?: string; description?: string; dimensions?: Record<string, object>; measures?: Record<string, object> }>` | optional | Analytics dataset translations keyed by dataset name |
-| **reports** | `Record<string, { label?: string; description?: string }>` | optional | Report translations keyed by report name |
+| **reports** | `Record<string, { label?: string; description?: string; blocks?: Record<string, object> }>` | optional | Report translations keyed by report name |
 | **pages** | `Record<string, { label?: string; description?: string; title?: string; subtitle?: string; … }>` | optional | Page translations keyed by page name |
 | **flows** | `Record<string, { label?: string; successMessage?: string; errorMessage?: string; screens?: Record<string, object>; … }>` | optional | Screen-flow translations keyed by flow name |
 | **positions** | `Record<string, { label?: string; description?: string }>` | optional | Position translations keyed by position name |
@@ -195,7 +197,7 @@ Translation data for a single object
 | **label** | `string` | optional | Translated singular label |
 | **pluralLabel** | `string` | optional | Translated plural label |
 | **description** | `string` | optional | Translated object description |
-| **fields** | `Record<string, { label?: string; help?: string; placeholder?: string; options?: Record<string, string> }>` | optional | Field-level translations |
+| **fields** | `Record<string, { label?: string; help?: string; placeholder?: string; options?: Record<string, string>; … }>` | optional | Field-level translations |
 | **_views** | `Record<string, { label?: string; description?: string; title?: string; emptyState?: object; … }>` | optional | View translations keyed by view name |
 | **_actions** | `Record<string, { label?: string; description?: string; confirmText?: string; successMessage?: string; … }>` | optional | Action translations keyed by action name |
 | **_sections** | `Record<string, { label?: string; description?: string; fields?: Record<string, object> }>` | optional | Section translations keyed by section name |
@@ -254,6 +256,7 @@ Translation data for a single object
 | :--- | :--- | :--- | :--- |
 | **label** | `string` | optional | Translated report label — overlays the report's own `label` |
 | **description** | `string` | optional | Translated report description — overlays the report's own `description` |
+| **blocks** | `Record<string, { label?: string; description?: string }>` | optional | Joined report block translations keyed by block name |
 
 ### Nested Shape: `PlatformTranslationData.pages[string]`
 
@@ -334,7 +337,7 @@ Served translation data — the platform groups the browser reads, without the s
 | **globalActions** | `Record<string, { label?: string; description?: string; confirmText?: string; successMessage?: string; … }>` | optional | Global action translations keyed by action name |
 | **dashboards** | `Record<string, { label?: string; description?: string; actions?: Record<string, object>; widgets?: Record<string, object>; … }>` | optional | Dashboard translations keyed by dashboard name |
 | **datasets** | `Record<string, { label?: string; description?: string; dimensions?: Record<string, object>; measures?: Record<string, object> }>` | optional | Analytics dataset translations keyed by dataset name |
-| **reports** | `Record<string, { label?: string; description?: string }>` | optional | Report translations keyed by report name |
+| **reports** | `Record<string, { label?: string; description?: string; blocks?: Record<string, object> }>` | optional | Report translations keyed by report name |
 | **pages** | `Record<string, { label?: string; description?: string; title?: string; subtitle?: string; … }>` | optional | Page translations keyed by page name |
 | **flows** | `Record<string, { label?: string; successMessage?: string; errorMessage?: string; screens?: Record<string, object>; … }>` | optional | Screen-flow translations keyed by flow name |
 | **positions** | `Record<string, { label?: string; description?: string }>` | optional | Position translations keyed by position name |
@@ -351,7 +354,7 @@ Translation data for a single object
 | **label** | `string` | optional | Translated singular label |
 | **pluralLabel** | `string` | optional | Translated plural label |
 | **description** | `string` | optional | Translated object description |
-| **fields** | `Record<string, { label?: string; help?: string; placeholder?: string; options?: Record<string, string> }>` | optional | Field-level translations |
+| **fields** | `Record<string, { label?: string; help?: string; placeholder?: string; options?: Record<string, string>; … }>` | optional | Field-level translations |
 | **_views** | `Record<string, { label?: string; description?: string; title?: string; emptyState?: object; … }>` | optional | View translations keyed by view name |
 | **_actions** | `Record<string, { label?: string; description?: string; confirmText?: string; successMessage?: string; … }>` | optional | Action translations keyed by action name |
 | **_sections** | `Record<string, { label?: string; description?: string; fields?: Record<string, object> }>` | optional | Section translations keyed by section name |
@@ -410,6 +413,7 @@ Translation data for a single object
 | :--- | :--- | :--- | :--- |
 | **label** | `string` | optional | Translated report label — overlays the report's own `label` |
 | **description** | `string` | optional | Translated report description — overlays the report's own `description` |
+| **blocks** | `Record<string, { label?: string; description?: string }>` | optional | Joined report block translations keyed by block name |
 
 ### Nested Shape: `ServedTranslationData.pages[string]`
 
@@ -552,7 +556,7 @@ Per-app translation data for objects, apps, and UI messages
 | **globalActions** | `Record<string, { label?: string; description?: string; confirmText?: string; successMessage?: string; … }>` | optional | Global action translations keyed by action name |
 | **dashboards** | `Record<string, { label?: string; description?: string; actions?: Record<string, object>; widgets?: Record<string, object>; … }>` | optional | Dashboard translations keyed by dashboard name |
 | **datasets** | `Record<string, { label?: string; description?: string; dimensions?: Record<string, object>; measures?: Record<string, object> }>` | optional | Analytics dataset translations keyed by dataset name |
-| **reports** | `Record<string, { label?: string; description?: string }>` | optional | Report translations keyed by report name |
+| **reports** | `Record<string, { label?: string; description?: string; blocks?: Record<string, object> }>` | optional | Report translations keyed by report name |
 | **pages** | `Record<string, { label?: string; description?: string; title?: string; subtitle?: string; … }>` | optional | Page translations keyed by page name |
 | **flows** | `Record<string, { label?: string; successMessage?: string; errorMessage?: string; screens?: Record<string, object>; … }>` | optional | Screen-flow translations keyed by flow name |
 | **positions** | `Record<string, { label?: string; description?: string }>` | optional | Position translations keyed by position name |
@@ -569,7 +573,7 @@ Translation data for a single object
 | **label** | `string` | optional | Translated singular label |
 | **pluralLabel** | `string` | optional | Translated plural label |
 | **description** | `string` | optional | Translated object description |
-| **fields** | `Record<string, { label?: string; help?: string; placeholder?: string; options?: Record<string, string> }>` | optional | Field-level translations |
+| **fields** | `Record<string, { label?: string; help?: string; placeholder?: string; options?: Record<string, string>; … }>` | optional | Field-level translations |
 | **_views** | `Record<string, { label?: string; description?: string; title?: string; emptyState?: object; … }>` | optional | View translations keyed by view name |
 | **_actions** | `Record<string, { label?: string; description?: string; confirmText?: string; successMessage?: string; … }>` | optional | Action translations keyed by action name |
 | **_sections** | `Record<string, { label?: string; description?: string; fields?: Record<string, object> }>` | optional | Section translations keyed by section name |
@@ -628,6 +632,7 @@ Translation data for a single object
 | :--- | :--- | :--- | :--- |
 | **label** | `string` | optional | Translated report label — overlays the report's own `label` |
 | **description** | `string` | optional | Translated report description — overlays the report's own `description` |
+| **blocks** | `Record<string, { label?: string; description?: string }>` | optional | Joined report block translations keyed by block name |
 
 ### Nested Shape: `TranslationData.pages[string]`
 
@@ -729,7 +734,7 @@ One locale of translations — the `translation` metadata type
 | **globalActions** | `Record<string, { label?: string; description?: string; confirmText?: string; successMessage?: string; … }>` | optional | Global action translations keyed by action name |
 | **dashboards** | `Record<string, { label?: string; description?: string; actions?: Record<string, object>; widgets?: Record<string, object>; … }>` | optional | Dashboard translations keyed by dashboard name |
 | **datasets** | `Record<string, { label?: string; description?: string; dimensions?: Record<string, object>; measures?: Record<string, object> }>` | optional | Analytics dataset translations keyed by dataset name |
-| **reports** | `Record<string, { label?: string; description?: string }>` | optional | Report translations keyed by report name |
+| **reports** | `Record<string, { label?: string; description?: string; blocks?: Record<string, object> }>` | optional | Report translations keyed by report name |
 | **pages** | `Record<string, { label?: string; description?: string; title?: string; subtitle?: string; … }>` | optional | Page translations keyed by page name |
 | **flows** | `Record<string, { label?: string; successMessage?: string; errorMessage?: string; screens?: Record<string, object>; … }>` | optional | Screen-flow translations keyed by flow name |
 | **positions** | `Record<string, { label?: string; description?: string }>` | optional | Position translations keyed by position name |
@@ -756,7 +761,7 @@ Translation data for a single object
 | **label** | `string` | optional | Translated singular label |
 | **pluralLabel** | `string` | optional | Translated plural label |
 | **description** | `string` | optional | Translated object description |
-| **fields** | `Record<string, { label?: string; help?: string; placeholder?: string; options?: Record<string, string> }>` | optional | Field-level translations |
+| **fields** | `Record<string, { label?: string; help?: string; placeholder?: string; options?: Record<string, string>; … }>` | optional | Field-level translations |
 | **_views** | `Record<string, { label?: string; description?: string; title?: string; emptyState?: object; … }>` | optional | View translations keyed by view name |
 | **_actions** | `Record<string, { label?: string; description?: string; confirmText?: string; successMessage?: string; … }>` | optional | Action translations keyed by action name |
 | **_sections** | `Record<string, { label?: string; description?: string; fields?: Record<string, object> }>` | optional | Section translations keyed by section name |
@@ -815,6 +820,7 @@ Translation data for a single object
 | :--- | :--- | :--- | :--- |
 | **label** | `string` | optional | Translated report label — overlays the report's own `label` |
 | **description** | `string` | optional | Translated report description — overlays the report's own `description` |
+| **blocks** | `Record<string, { label?: string; description?: string }>` | optional | Joined report block translations keyed by block name |
 
 ### Nested Shape: `TranslationItem.pages[string]`
 
diff --git a/docs/audits/2026-07-unknown-key-strictness-ledger.counts/system.md b/docs/audits/2026-07-unknown-key-strictness-ledger.counts/system.md
index 9c535ae34bf..eb3d3289225 100644
--- a/docs/audits/2026-07-unknown-key-strictness-ledger.counts/system.md
+++ b/docs/audits/2026-07-unknown-key-strictness-ledger.counts/system.md
@@ -19,4 +19,4 @@ hand-patch a number here** — fix the code or the verdict and regenerate.
 
 | Dir | Sites |
 |---|---|
-| `system/` | 383 |
+| `system/` | 384 |
diff --git a/examples/app-crm/src/translations/crm.translation.ts b/examples/app-crm/src/translations/crm.translation.ts
index f11cf234fd4..38af04a306b 100644
--- a/examples/app-crm/src/translations/crm.translation.ts
+++ b/examples/app-crm/src/translations/crm.translation.ts
@@ -92,6 +92,13 @@ export const CrmTranslationBundle = defineTranslationBundle({
 
   'zh-CN': {
     objects: {
+      // The inline product grid's heading on the opportunity form. The field
+      // lives on the line item, so the key is the line item's.
+      crm_opportunity_line_item: {
+        fields: {
+          opportunity: { inlineTitle: '产品明细' },
+        },
+      },
       crm_account: {
         label: '客户',
         pluralLabel: '客户列表',
diff --git a/examples/app-showcase/src/system/translations/index.ts b/examples/app-showcase/src/system/translations/index.ts
index 09cce8f102e..b00559fb8f3 100644
--- a/examples/app-showcase/src/system/translations/index.ts
+++ b/examples/app-showcase/src/system/translations/index.ts
@@ -782,6 +782,9 @@ export const ShowcaseTranslationBundle = {
       showcase_expense_line: {
         fields: {
           incurred_at: { label: '发生时间' },
+          // The inline grid heading on the expense report's form — a key born
+          // with its slot, so it is translated at birth like the label above.
+          expense_report: { inlineTitle: '费用明细' },
         },
       },
       // See the `en` side for why this entry translates exactly ONE field and
@@ -789,6 +792,8 @@ export const ShowcaseTranslationBundle = {
       showcase_invoice_line: {
         fields: {
           service_start: { label: '服务开始时间' },
+          // The inline grid heading on the invoice form, translated at birth.
+          invoice: { inlineTitle: '发票明细' },
         },
       },
       showcase_preference: {
@@ -1349,7 +1354,15 @@ export const ShowcaseTranslationBundle = {
     reports: {
       showcase_hours_by_status: { label: '按状态统计工时（汇总）', description: '按任务状态分组的预计工时。' },
       showcase_status_priority_matrix: { label: '状态 × 优先级（矩阵）', description: '按状态和优先级交叉统计的预计工时。' },
-      showcase_task_overview: { label: '任务概览（联合）', description: '将多个任务子报表堆叠在一个联合视图中。' },
+      showcase_task_overview: {
+        label: '任务概览（联合）',
+        description: '将多个任务子报表堆叠在一个联合视图中。',
+        // The joined report's block headings, keyed by block `name`.
+        blocks: {
+          open_block: { label: '未完成任务' },
+          done_block: { label: '已完成任务' },
+        },
+      },
       showcase_hours_by_status_chart: { label: '按状态统计工时（图表）', description: '以柱状图展示按状态统计的预计工时。' },
     },
   },
diff --git a/examples/app-showcase/test/zh-cn-report-blocks-inline-titles.test.ts b/examples/app-showcase/test/zh-cn-report-blocks-inline-titles.test.ts
new file mode 100644
index 00000000000..bd887837061
--- /dev/null
+++ b/examples/app-showcase/test/zh-cn-report-blocks-inline-titles.test.ts
@@ -0,0 +1,51 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+
+/**
+ * Under zh-CN, the showcase's two authored headings that had no translation
+ * slot are served translated:
+ *
+ *  - the joined report `showcase_task_overview` — its title was translated
+ *    while its block headings ("Open Tasks", "Completed Tasks") stayed English;
+ *  - the inline line-item grids on the invoice and expense-report create forms,
+ *    headed by the child field's `inlineTitle` ("Line Items", "Expense Lines").
+ *
+ * Both reach the console as the served document: the joined report renderer
+ * draws `block.label` off `GET /meta/report`, and the console's inline-subform
+ * pass copies the child field's `inlineTitle` off `GET /meta/object`. So the
+ * pin is the translator applied to the app's own metadata with the app's own
+ * bundle, exactly what the REST boundary does per request locale.
+ */
+import { describe, expect, it } from 'vitest';
+import { translateMetadataDocument, type TranslationBundle } from '@objectstack/spec/system';
+import { TaskOverviewReport } from '../src/ui/reports/index.js';
+import { InvoiceLine } from '../src/data/objects/invoice.object.js';
+import { ExpenseLine } from '../src/data/objects/expense-report.object.js';
+import { ShowcaseTranslationBundle } from '../src/system/translations/index.js';
+
+const bundle = ShowcaseTranslationBundle as unknown as TranslationBundle;
+const zh = { locale: 'zh-CN' };
+
+describe('showcase under zh-CN — authored headings with a slot of their own', () => {
+  it('serves the joined report\'s block headings translated, under its translated title', () => {
+    const out = translateMetadataDocument('report', TaskOverviewReport, bundle, zh);
+    expect(out.label).toBe('任务概览（联合）');
+    expect(out.blocks.map((b: { name: string; label: unknown }) => [b.name, b.label])).toEqual([
+      ['open_block', '未完成任务'],
+      ['done_block', '已完成任务'],
+    ]);
+  });
+
+  it('serves the invoice and expense-report inline grid headings translated', () => {
+    const invoiceLine = translateMetadataDocument('object', InvoiceLine, bundle, zh);
+    expect(invoiceLine.fields.invoice.inlineTitle).toBe('发票明细');
+    const expenseLine = translateMetadataDocument('object', ExpenseLine, bundle, zh);
+    expect(expenseLine.fields.expense_report.inlineTitle).toBe('费用明细');
+  });
+
+  it('leaves the authored English in place for a locale the bundle does not carry', () => {
+    const out = translateMetadataDocument('report', TaskOverviewReport, bundle, { locale: 'en' });
+    expect(out.blocks.map((b: { label: unknown }) => b.label)).toEqual(['Open Tasks', 'Completed Tasks']);
+    expect(translateMetadataDocument('object', InvoiceLine, bundle, { locale: 'en' }).fields.invoice.inlineTitle)
+      .toBe('Line Items');
+  });
+});
diff --git a/packages/cli/src/utils/i18n-coverage.ts b/packages/cli/src/utils/i18n-coverage.ts
index 321ccb3f9a1..5afbd13d342 100644
--- a/packages/cli/src/utils/i18n-coverage.ts
+++ b/packages/cli/src/utils/i18n-coverage.ts
@@ -353,7 +353,8 @@ const COVERAGE_SOURCE: Record<ExpectedEntry['source'], CoverageIssue['source']>
   // the `dashboard` bucket: the string is defined once, not once per
   // presentation.
   dataset: 'dataset',
-  // Report copy (`reports.<r>.label` / `.description`) — the author's own
+  // Report copy (`reports.<r>.label` / `.description`, and a joined report's
+  // block headings at `reports.<r>.blocks.<b>.*`) — the author's own
   // reports, listed by these two strings on the app's report index and headed
   // by the label on the report page, so it keeps its own bucket and reports as
   // `i18n/missing-report` rather than folding into `dashboard`.
diff --git a/packages/cli/src/utils/i18n-extract.ts b/packages/cli/src/utils/i18n-extract.ts
index d17f41e4da5..ad6a953488e 100644
--- a/packages/cli/src/utils/i18n-extract.ts
+++ b/packages/cli/src/utils/i18n-extract.ts
@@ -1390,6 +1390,9 @@ export function collectExpectedEntries(
           { objectName },
         );
         pushOptional(out, ['objects', objectName, 'fields', fieldName, 'placeholder'], field.placeholder, 'field', { objectName });
+        // The inline child grid's heading, drawn on the PARENT's form but
+        // addressed by the child field that declares it (`translateObject`).
+        pushOptional(out, ['objects', objectName, 'fields', fieldName, 'inlineTitle'], field.inlineTitle, 'field', { objectName });
 
         // Options — accept either `{value, label}[]` arrays or a record map.
         //
@@ -1871,8 +1874,9 @@ function walkPicklists(config: any, out: ExpectedEntry[]): void {
  * Emit the report copy surface:
  *
  *   reports.<name>.label / .description
+ *   reports.<name>.blocks.<block_name>.label / .description
  *
- * Read off the stack's `reports[]`. Served through `translateReport`,
+ * Read off the stack's `reports[]` and each joined report's `blocks[]`. Served through `translateReport`,
  * registered in `METADATA_DOCUMENT_TRANSLATORS`, so the REST boundary
  * localizes `GET /meta/report` (the list the console's report index and report
  * page read); this pass is the half that writes the skeleton and lets
@@ -1881,8 +1885,9 @@ function walkPicklists(config: any, out: ExpectedEntry[]): void {
  * `pushOptional` for both keys: a report's `description` is optional at the
  * authoring site, so a string nobody wrote is recorded without an `inline` and
  * never demanded as a translation. A report's `label` is required, so it is
- * always authored text. A joined report's block labels and the embedded
- * chart's copy are not on this face.
+ * always authored text. A block's `label` is optional (the renderer falls back
+ * to the block's machine `name`), so a block without one is recorded the same
+ * way and never demanded. The embedded chart's copy is not on this face.
  */
 function walkReports(config: any, out: ExpectedEntry[]): void {
   const reports: any[] = Array.isArray(config?.reports) ? config.reports : [];
@@ -1892,6 +1897,14 @@ function walkReports(config: any, out: ExpectedEntry[]): void {
     if (typeof name !== 'string' || name.length === 0) continue;
     pushOptional(out, ['reports', name, 'label'], report.label, 'report');
     pushOptional(out, ['reports', name, 'description'], report.description, 'report');
+    const blocks: any[] = Array.isArray(report.blocks) ? report.blocks : [];
+    for (const block of blocks) {
+      if (!block || typeof block !== 'object') continue;
+      const blockName = block.name;
+      if (typeof blockName !== 'string' || blockName.length === 0) continue;
+      pushOptional(out, ['reports', name, 'blocks', blockName, 'label'], block.label, 'report');
+      pushOptional(out, ['reports', name, 'blocks', blockName, 'description'], block.description, 'report');
+    }
   }
 }
 
diff --git a/packages/cli/test/i18n-block-inline-title-walk.test.ts b/packages/cli/test/i18n-block-inline-title-walk.test.ts
new file mode 100644
index 00000000000..9aa4812fe5b
--- /dev/null
+++ b/packages/cli/test/i18n-block-inline-title-walk.test.ts
@@ -0,0 +1,114 @@
+// Copyright (c) 2026 ObjectStack contributors. Apache-2.0 license.
+//
+// Two authored, user-visible labels the extractor did not walk:
+//
+//  - a joined report's block heading and caption
+//    (`reports.<name>.blocks.<block_name>.label` / `.description`);
+//  - a master-detail field's inline grid heading
+//    (`objects.<child>.fields.<field>.inlineTitle`).
+//
+// Both are served through their translators (`translateReport`,
+// `translateObject`), so without this walk `os i18n extract` scaffolded no key
+// for them and `os i18n check` measured a debt of zero while a zh-CN user read
+// them in English.
+
+import { describe, it, expect } from 'vitest';
+import { collectExpectedEntries, extractTranslations } from '../src/utils/i18n-extract.js';
+import { computeI18nCoverage } from '../src/utils/i18n-coverage.js';
+import { TranslationDataSchema } from '@objectstack/spec/system';
+
+const config = () => ({
+  objects: [
+    {
+      name: 'invoice_line',
+      label: 'Invoice Line',
+      fields: {
+        invoice: { type: 'master_detail', label: 'Invoice', reference: 'invoice', inlineEdit: 'grid', inlineTitle: 'Line Items' },
+        // No inlineTitle: the grid is headed by the child's label, nothing to demand.
+        amount: { type: 'currency', label: 'Amount' },
+      },
+    },
+  ],
+  reports: [
+    {
+      name: 'task_overview',
+      label: 'Task Overview',
+      type: 'joined',
+      blocks: [
+        { name: 'open_block', label: 'Open Tasks', description: 'Still in flight', type: 'summary', dataset: 'tasks', values: ['n'] },
+        // No label: the renderer falls back to the block's machine name.
+        { name: 'done_block', type: 'summary', dataset: 'tasks', values: ['n'] },
+      ],
+    },
+  ],
+});
+
+const byKey = () => new Map(collectExpectedEntries(config()).map((e) => [e.path.join('.'), e]));
+
+describe('i18n extract — joined report blocks', () => {
+  it('walks each block\'s label and description under the report', () => {
+    const keys = [...byKey().keys()].filter((k) => k.startsWith('reports.task_overview.blocks.')).sort();
+    expect(keys).toEqual([
+      'reports.task_overview.blocks.done_block.description',
+      'reports.task_overview.blocks.done_block.label',
+      'reports.task_overview.blocks.open_block.description',
+      'reports.task_overview.blocks.open_block.label',
+    ]);
+  });
+
+  it('seeds authored text and records an unwritten string without demanding it', () => {
+    const entries = byKey();
+    expect(entries.get('reports.task_overview.blocks.open_block.label'))
+      .toMatchObject({ sourceValue: 'Open Tasks', inline: 'Open Tasks', source: 'report' });
+    expect(entries.get('reports.task_overview.blocks.open_block.description'))
+      .toMatchObject({ sourceValue: 'Still in flight', source: 'report' });
+    const unwritten = entries.get('reports.task_overview.blocks.done_block.label');
+    expect(unwritten?.sourceValue).toBeUndefined();
+    expect(unwritten?.inline).toBeUndefined();
+  });
+});
+
+describe('i18n extract — a field\'s inlineTitle', () => {
+  it('walks the heading on the child field that declares it, and only there', () => {
+    const entries = byKey();
+    expect(entries.get('objects.invoice_line.fields.invoice.inlineTitle'))
+      .toMatchObject({ sourceValue: 'Line Items', inline: 'Line Items', source: 'field' });
+    expect(entries.get('objects.invoice_line.fields.amount.inlineTitle')?.inline).toBeUndefined();
+  });
+});
+
+describe('i18n extract + check — both slots', () => {
+  it('`TranslationDataSchema` accepts a bundle written at the extracted paths', () => {
+    const out = extractTranslations(config(), { locales: ['zh-CN'] });
+    const zh = out.bundles['zh-CN'] as any;
+    expect(zh?.reports?.task_overview?.blocks?.open_block?.label).toBeDefined();
+    expect(zh?.objects?.invoice_line?.fields?.invoice?.inlineTitle).toBeDefined();
+    expect(TranslationDataSchema.safeParse({ reports: zh.reports, objects: zh.objects }).success).toBe(true);
+  });
+
+  it('reports an untranslated block heading and inline heading, and clears them once translated', () => {
+    const coverage = (translations: unknown[]) => computeI18nCoverage({
+      ...config(),
+      i18n: { supportedLocales: ['en', 'zh-CN'] },
+      translations,
+    } as any).issues.filter((i) => i.locale === 'zh-CN').map((i) => i.key);
+
+    const before = coverage([{ 'zh-CN': { reports: { task_overview: { label: '任务概览' } } } }]);
+    expect(before).toContain('reports.task_overview.blocks.open_block.label');
+    expect(before).toContain('reports.task_overview.blocks.open_block.description');
+    expect(before).toContain('objects.invoice_line.fields.invoice.inlineTitle');
+    // Nothing authored ⇒ nothing to translate.
+    expect(before).not.toContain('reports.task_overview.blocks.done_block.label');
+    expect(before).not.toContain('objects.invoice_line.fields.amount.inlineTitle');
+
+    const after = coverage([{
+      'zh-CN': {
+        reports: { task_overview: { label: '任务概览', blocks: { open_block: { label: '未完成任务', description: '仍在进行中' } } } },
+        objects: { invoice_line: { fields: { invoice: { inlineTitle: '发票明细' } } } },
+      },
+    }]);
+    expect(after).not.toContain('reports.task_overview.blocks.open_block.label');
+    expect(after).not.toContain('reports.task_overview.blocks.open_block.description');
+    expect(after).not.toContain('objects.invoice_line.fields.invoice.inlineTitle');
+  });
+});
diff --git a/packages/spec/api-surface/system.json b/packages/spec/api-surface/system.json
index 9297c68fbf7..982d40c2cbe 100644
--- a/packages/spec/api-surface/system.json
+++ b/packages/spec/api-surface/system.json
@@ -559,6 +559,7 @@
     "RenderOperationMessageOptions (interface)",
     "RenderValidationMessageInput (interface)",
     "RenderValidationMessageOptions (interface)",
+    "ReportBlockLike (interface)",
     "ReportLike (interface)",
     "ResolveOptions (interface)",
     "ResolvedBook (interface)",
diff --git a/packages/spec/authorable-surface/system.json b/packages/spec/authorable-surface/system.json
index 5230dc0fbb4..e2dcb63e47c 100644
--- a/packages/spec/authorable-surface/system.json
+++ b/packages/spec/authorable-surface/system.json
@@ -441,6 +441,7 @@
     "system/FieldEncryption:fieldName",
     "system/FieldEncryption:indexable",
     "system/FieldTranslation:help",
+    "system/FieldTranslation:inlineTitle",
     "system/FieldTranslation:label",
     "system/FieldTranslation:options",
     "system/FieldTranslation:placeholder",
diff --git a/packages/spec/export-origins/system.json b/packages/spec/export-origins/system.json
index 935a29155b9..d5a7c120bc8 100644
--- a/packages/spec/export-origins/system.json
+++ b/packages/spec/export-origins/system.json
@@ -535,6 +535,7 @@
     "RenderOperationMessageOptions": "src/system/operation-message.ts#RenderOperationMessageOptions (interface)",
     "RenderValidationMessageInput": "src/system/validation-message.ts#RenderValidationMessageInput (interface)",
     "RenderValidationMessageOptions": "src/system/validation-message.ts#RenderValidationMessageOptions (interface)",
+    "ReportBlockLike": "src/system/i18n-resolver.ts#ReportBlockLike (interface)",
     "ReportLike": "src/system/i18n-resolver.ts#ReportLike (interface)",
     "ResolveOptions": "src/system/i18n-resolver.ts#ResolveOptions (interface)",
     "ResolvedBook": "src/system/book.zod.ts#ResolvedBook (interface)",
diff --git a/packages/spec/liveness/state-counts/translation.md b/packages/spec/liveness/state-counts/translation.md
index bba0cf8b57d..3979c0c9e77 100644
--- a/packages/spec/liveness/state-counts/translation.md
+++ b/packages/spec/liveness/state-counts/translation.md
@@ -12,4 +12,4 @@ committed anywhere: `check:liveness` sums the shards when it reads them.
 
 | Type | live | exp | elsewhere | dead | planned | classified |
 |---|---|---|---|---|---|---|
-| `translation` | 36 | 0 | 0 | 0 | 0 | 36 |
+| `translation` | 38 | 0 | 0 | 0 | 0 | 38 |
diff --git a/packages/spec/liveness/translation.json b/packages/spec/liveness/translation.json
index 0c2ea7b8c3f..e8e745cbf50 100644
--- a/packages/spec/liveness/translation.json
+++ b/packages/spec/liveness/translation.json
@@ -123,6 +123,26 @@
           "verifiedAt": "2026-10-25",
           "evidence": "packages/spec/src/system/i18n-resolver.ts#lookupReportAttr (`reports.<name>.description`, read by translateReport)",
           "note": "Overlays the served report's own `description`."
+        },
+        "blocks": {
+          "status": "live",
+          "verifiedAt": "2026-10-27",
+          "evidence": "packages/spec/src/system/i18n-resolver.ts#translateReportBlocks (`reports.<name>.blocks.<block_name>`, read by translateReport per joined block, keyed by the block's required `name`)",
+          "note": "A joined report's block heading and caption, drawn by the joined renderer off the served report. Seeded LIVE with its reader in the same change; the catalog yields per block to a string an org re-authored on the packaged report (ADR-0029 D9.2a).",
+          "children": {
+            "label": {
+              "status": "live",
+              "verifiedAt": "2026-10-27",
+              "evidence": "packages/spec/src/system/i18n-resolver.ts#lookupReportBlockAttr (`reports.<name>.blocks.<block_name>.label`, read by translateReportBlocks)",
+              "note": "Overlays the served block's own `label`."
+            },
+            "description": {
+              "status": "live",
+              "verifiedAt": "2026-10-27",
+              "evidence": "packages/spec/src/system/i18n-resolver.ts#lookupReportBlockAttr (`reports.<name>.blocks.<block_name>.description`, read by translateReportBlocks)",
+              "note": "Overlays the served block's own `description`."
+            }
+          }
         }
       }
     },
diff --git a/packages/spec/src/system/i18n-field-inline-title.test.ts b/packages/spec/src/system/i18n-field-inline-title.test.ts
new file mode 100644
index 00000000000..3e250509775
--- /dev/null
+++ b/packages/spec/src/system/i18n-field-inline-title.test.ts
@@ -0,0 +1,112 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+//
+// `objects.<child>.fields.<field>.inlineTitle` — the heading of the inline
+// child grid a master-detail field draws on its PARENT's form, and the
+// translator that overlays it on the served child object.
+//
+// Before this slot existed, every label of a zh-CN create form was Chinese
+// except the inline child-grid headings, which printed the authored
+// `inlineTitle` verbatim: the bundle had no key to put them under, so the
+// coverage gate had nothing to miss.
+
+import { describe, it, expect } from 'vitest';
+import {
+  ObjectTranslationDataSchema,
+  TranslationDataSchema,
+  type TranslationBundle,
+} from './translation.zod';
+import { translateMetadataDocument, translateObject } from './i18n-resolver';
+import { FieldSchema } from '../data/field.zod';
+
+const PACKAGED = {
+  name: 'contract_version',
+  label: 'Contract Version',
+  pluralLabel: 'Versions',
+  fields: {
+    contract: {
+      name: 'contract',
+      type: 'master_detail',
+      label: 'Contract',
+      reference: 'contract',
+      inlineEdit: 'grid',
+      inlineTitle: 'Versions',
+    },
+    amendment: {
+      name: 'amendment',
+      type: 'lookup',
+      label: 'Amendment',
+      reference: 'amendment',
+      inlineEdit: 'grid',
+      inlineTitle: 'Amended Versions',
+    },
+  },
+};
+
+const BUNDLE: TranslationBundle = {
+  'zh-CN': {
+    objects: {
+      contract_version: {
+        fields: {
+          contract: { label: '合同', inlineTitle: '版本' },
+        },
+      },
+    },
+  },
+};
+
+const clone = <V>(value: V): V => JSON.parse(JSON.stringify(value));
+const fieldsOf = (out: unknown) => (out as { fields: Record<string, Record<string, unknown>> }).fields;
+
+describe('FieldTranslationSchema — inlineTitle', () => {
+  it('accepts the slot on a field translation, at the bundle and the per-object doors', () => {
+    expect(TranslationDataSchema.safeParse(BUNDLE['zh-CN']).success).toBe(true);
+    expect(ObjectTranslationDataSchema.safeParse({ fields: { contract: { inlineTitle: '版本' } } }).success).toBe(true);
+  });
+
+  it('refuses a non-string heading', () => {
+    const result = TranslationDataSchema.safeParse({
+      objects: { contract_version: { fields: { contract: { inlineTitle: { 'zh-CN': '版本' } } } } },
+    });
+    expect(result.success).toBe(false);
+    expect(result.error!.issues[0]).toMatchObject({
+      code: 'invalid_type',
+      path: ['objects', 'contract_version', 'fields', 'contract', 'inlineTitle'],
+    });
+  });
+});
+
+describe('translateObject — a field\'s inlineTitle', () => {
+  it('serves the translated heading on the child field, through the type dispatch, with no unrecognized key', () => {
+    const fields = fieldsOf(translateMetadataDocument('object', clone(PACKAGED), BUNDLE, { locale: 'zh-CN' }));
+    expect(fields.contract.inlineTitle).toBe('版本');
+    expect(fields.contract.label).toBe('合同');
+    const parsed = FieldSchema.safeParse(fields.contract);
+    expect(parsed.success ? [] : parsed.error.issues.filter((i) => i.code === 'unrecognized_keys')).toEqual([]);
+  });
+
+  it('keeps an untranslated heading as authored — never the child object\'s plural label', () => {
+    const fields = fieldsOf(translateObject(clone(PACKAGED), BUNDLE, { locale: 'zh-CN' }));
+    expect(fields.amendment.inlineTitle).toBe('Amended Versions');
+  });
+
+  it('applies the BCP-47 ladder and the fallback chain', () => {
+    expect(fieldsOf(translateObject(clone(PACKAGED), BUNDLE, { locale: 'zh' })).contract.inlineTitle).toBe('版本');
+    expect(fieldsOf(translateObject(clone(PACKAGED), BUNDLE, { locale: 'fr-FR', fallbackChain: ['zh-CN'] })).contract.inlineTitle)
+      .toBe('版本');
+  });
+
+  describe('the catalog loses to an explicit override (ADR-0029 D9.2a)', () => {
+    it('applies while the served heading still equals the packaged field\'s', () => {
+      const fields = fieldsOf(translateObject(clone(PACKAGED), BUNDLE, { locale: 'zh-CN', packagedBase: PACKAGED }));
+      expect(fields.contract.inlineTitle).toBe('版本');
+    });
+
+    it('yields to a heading the tenant re-authored, and still translates the field\'s label', () => {
+      const served = clone(PACKAGED);
+      served.fields.contract.inlineTitle = 'Revisions (ours)';
+      const fields = fieldsOf(translateObject(served, BUNDLE, { locale: 'zh-CN', packagedBase: PACKAGED }));
+      expect(fields.contract.inlineTitle).toBe('Revisions (ours)');
+      expect(fields.contract.label).toBe('合同');
+    });
+  });
+});
diff --git a/packages/spec/src/system/i18n-report-blocks.test.ts b/packages/spec/src/system/i18n-report-blocks.test.ts
new file mode 100644
index 00000000000..b7680edf651
--- /dev/null
+++ b/packages/spec/src/system/i18n-report-blocks.test.ts
@@ -0,0 +1,138 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+//
+// `reports.<name>.blocks.<block_name>.…` — a joined report's block copy, and
+// the translator that overlays it on the served `report` document.
+//
+// Before this slot existed, a localized tenant opening a joined report saw a
+// translated report title over block headings left in the authoring language:
+// the bundle had nowhere to put them, and `.strict()` refused a key a
+// translator invented.
+
+import { describe, it, expect } from 'vitest';
+import {
+  TranslationDataSchema,
+  TranslationItemSchema,
+  PlatformTranslationDataSchema,
+  type TranslationBundle,
+} from './translation.zod';
+import { translateMetadataDocument, translateReport } from './i18n-resolver';
+// Parsed by the authoring schema rather than hand-shaped, so a translator
+// reading a member the schema does not carry cannot pass here.
+import { ReportSchema } from '../ui/report.zod';
+
+const joined = () => ReportSchema.parse({
+  name: 'task_overview',
+  label: 'Task Overview',
+  type: 'joined',
+  blocks: [
+    { name: 'open_block', label: 'Open Tasks', description: 'Still in flight', type: 'summary', dataset: 'tasks', rows: ['status'], values: ['n'] },
+    { name: 'done_block', label: 'Completed Tasks', type: 'summary', dataset: 'tasks', rows: ['status'], values: ['n'] },
+  ],
+}) as any;
+
+const bundle: TranslationBundle = {
+  'zh-CN': {
+    reports: {
+      task_overview: {
+        label: '任务概览',
+        blocks: {
+          open_block: { label: '未完成任务', description: '仍在进行中' },
+          done_block: { label: '已完成任务' },
+        },
+      },
+    },
+  },
+};
+
+describe('TranslationDataSchema — reports.<name>.blocks', () => {
+  it('accepts the slot at all three doors — bundle entry, platform bundle and registered item', () => {
+    expect(TranslationDataSchema.safeParse(bundle['zh-CN']).success).toBe(true);
+    expect(PlatformTranslationDataSchema.safeParse(bundle['zh-CN']).success).toBe(true);
+    expect(TranslationItemSchema.safeParse({ locale: 'zh-CN', ...bundle['zh-CN'] }).success).toBe(true);
+  });
+
+  it('closes a block entry at `label` and `description`', () => {
+    const result = TranslationDataSchema.safeParse({
+      reports: { task_overview: { blocks: { open_block: { dataset: 'tasks' } } } },
+    });
+    expect(result.success).toBe(false);
+    expect(result.error!.issues.map((i) => i.code)).toContain('unrecognized_keys');
+  });
+
+  it('renames `title` onto `label` inside a block entry', () => {
+    const result = TranslationDataSchema.safeParse({
+      reports: { task_overview: { blocks: { open_block: { title: '未完成任务' } } } },
+    });
+    expect(result.success).toBe(false);
+    const issue = result.error!.issues[0];
+    expect(issue).toMatchObject({ code: 'unrecognized_keys', keys: ['title'], path: ['reports', 'task_overview', 'blocks', 'open_block'] });
+    expect(issue.message).toContain('`title` → `label`');
+  });
+});
+
+describe('translateReport — joined blocks', () => {
+  it('overlays each block heading and caption, keyed by block name', () => {
+    const out = translateMetadataDocument('report', joined(), bundle, { locale: 'zh-CN' }) as any;
+    expect(out.label).toBe('任务概览');
+    expect(out.blocks.map((b: any) => b.label)).toEqual(['未完成任务', '已完成任务']);
+    expect(out.blocks[0].description).toBe('仍在进行中');
+    // Identity and the selection ride through untouched.
+    expect(out.blocks.map((b: any) => b.name)).toEqual(['open_block', 'done_block']);
+    expect(out.blocks[0].dataset).toBe('tasks');
+    expect(out.blocks[1].description).toBeUndefined();
+  });
+
+  it('translates the blocks when the bundle addresses only the blocks', () => {
+    const blocksOnly: TranslationBundle = {
+      'zh-CN': { reports: { task_overview: { blocks: { done_block: { label: '已完成任务' } } } } },
+    };
+    const doc = joined();
+    const out = translateReport(doc, blocksOnly, { locale: 'zh-CN' }) as any;
+    expect(out.label).toBe('Task Overview');
+    // An unaddressed block rides through as the same reference.
+    expect(out.blocks[0]).toBe(doc.blocks[0]);
+    expect(out.blocks[1].label).toBe('已完成任务');
+  });
+
+  it('applies the BCP-47 ladder and the fallback chain to blocks', () => {
+    expect((translateReport(joined(), bundle, { locale: 'zh' }) as any).blocks[1].label).toBe('已完成任务');
+    expect((translateReport(joined(), bundle, { locale: 'fr-FR', fallbackChain: ['zh-CN'] }) as any).blocks[1].label)
+      .toBe('已完成任务');
+  });
+
+  it('does not mutate the input, and returns the same reference when no block matched', () => {
+    const doc = joined();
+    const before = JSON.parse(JSON.stringify(doc));
+    translateReport(doc, bundle, { locale: 'zh-CN' });
+    expect(doc).toEqual(before);
+    const other: TranslationBundle = { 'zh-CN': { reports: { task_overview: { blocks: { gone_block: { label: '无' } } } } } };
+    expect(translateReport(doc, other, { locale: 'zh-CN' })).toBe(doc);
+  });
+
+  describe('the catalog loses to an explicit override (ADR-0029 D9.2a)', () => {
+    it('applies while a block still equals its packaged counterpart', () => {
+      const out = translateReport(joined(), bundle, { locale: 'zh-CN', packagedBase: joined() }) as any;
+      expect(out.blocks[0].label).toBe('未完成任务');
+    });
+
+    it('yields to a block heading an org re-authored, and still translates the rest', () => {
+      const edited = joined();
+      edited.blocks[0] = { ...edited.blocks[0], label: 'Open work (ours)' };
+      const out = translateReport(edited, bundle, { locale: 'zh-CN', packagedBase: joined() }) as any;
+      expect(out.blocks[0].label).toBe('Open work (ours)');
+      expect(out.blocks[0].description).toBe('仍在进行中');
+      expect(out.blocks[1].label).toBe('已完成任务');
+    });
+
+    it('treats a block the packaged report does not declare as authored after the fact', () => {
+      const added = joined();
+      added.blocks.push({ name: 'late_block', label: 'Late Tasks', type: 'summary', dataset: 'tasks', values: ['n'] });
+      const lateBundle: TranslationBundle = {
+        'zh-CN': { reports: { task_overview: { blocks: { late_block: { label: '逾期任务' } } } } },
+      };
+      expect(translateReport(added, lateBundle, { locale: 'zh-CN', packagedBase: joined() })).toBe(added);
+      // No base supplied — nothing is inferred and the catalog applies.
+      expect((translateReport(added, lateBundle, { locale: 'zh-CN' }) as any).blocks[2].label).toBe('逾期任务');
+    });
+  });
+});
diff --git a/packages/spec/src/system/i18n-resolver.ts b/packages/spec/src/system/i18n-resolver.ts
index 77823c09515..338707b36c2 100644
--- a/packages/spec/src/system/i18n-resolver.ts
+++ b/packages/spec/src/system/i18n-resolver.ts
@@ -1769,7 +1769,7 @@ function isOptionValue(value: unknown): value is string | number | boolean {
  */
 function packagedPart(
   parent: Record<string, unknown> | undefined,
-  key: 'widgets' | 'globalFilters' | 'options' | 'bulkActionDefs' | 'params' | 'sections' | 'fields',
+  key: 'widgets' | 'globalFilters' | 'options' | 'bulkActionDefs' | 'params' | 'sections' | 'fields' | 'blocks',
   matches: (candidate: Record<string, any>) => boolean,
 ): Record<string, unknown> | undefined {
   if (parent === undefined) return undefined;
@@ -2226,11 +2226,21 @@ export function translatePermissionSet<T extends SecurityCatalogItemLike>(
 // Report metadata resolver (label + description)
 // ────────────────────────────────────────────────────────────────────────────
 
+/** Minimal shape of a joined report block consumed by {@link translateReport}. */
+export interface ReportBlockLike {
+  /** `JoinedReportBlockSchema.name` — the key `reports.<name>.blocks` addresses. */
+  name?: string;
+  label?: unknown;
+  description?: unknown;
+  [key: string]: any;
+}
+
 /** Minimal shape of a report document consumed by {@link translateReport}. */
 export interface ReportLike {
   name: string;
   label?: unknown;
   description?: unknown;
+  blocks?: ReportBlockLike[];
   [key: string]: any;
 }
 
@@ -2248,17 +2258,73 @@ function lookupReportAttr(
   return undefined;
 }
 
+function lookupReportBlockAttr(
+  bundle: TranslationBundle | undefined,
+  name: string,
+  blockName: string,
+  attr: 'label' | 'description',
+  opts?: ResolveOptions,
+): string | undefined {
+  if (!bundle) return undefined;
+  for (const code of localeChain(opts)) {
+    const candidate = pickData(bundle, code)?.reports?.[name]?.blocks?.[blockName]?.[attr];
+    if (typeof candidate === 'string' && candidate.length > 0) return candidate;
+  }
+  return undefined;
+}
+
+/**
+ * Overlay `reports.<name>.blocks.<block_name>.{label,description}` onto a
+ * joined report's `blocks[]`, judging each block against its packaged
+ * counterpart (matched by `name`). Returns `undefined` when no block changed,
+ * so {@link translateReport} can keep handing back the input reference.
+ */
+function translateReportBlocks(
+  blocks: unknown,
+  bundle: TranslationBundle,
+  name: string,
+  base: Record<string, unknown> | undefined,
+  opts?: ResolveOptions,
+): ReportBlockLike[] | undefined {
+  if (!Array.isArray(blocks)) return undefined;
+  let changed = false;
+  const rebuilt = blocks.map((block: ReportBlockLike) => {
+    if (!block || typeof block !== 'object') return block;
+    const blockName = block.name;
+    if (typeof blockName !== 'string' || blockName.length === 0) return block;
+    const packagedBlock = packagedPart(base, 'blocks', (candidate) => candidate.name === blockName);
+    const label = valueOverridesPackagedBase(packagedBlock, 'label', block.label)
+      ? undefined
+      : lookupReportBlockAttr(bundle, name, blockName, 'label', opts);
+    const description = valueOverridesPackagedBase(packagedBlock, 'description', block.description)
+      ? undefined
+      : lookupReportBlockAttr(bundle, name, blockName, 'description', opts);
+    if (label === undefined && description === undefined) return block;
+    changed = true;
+    return {
+      ...block,
+      ...(label !== undefined ? { label } : {}),
+      ...(description !== undefined ? { description } : {}),
+    };
+  });
+  return changed ? rebuilt : undefined;
+}
+
 /**
  * Apply the active locale to a report metadata document — its `label` and
- * `description` against `reports.<name>.label` / `.description`. The input
- * document is not mutated, and it comes back as the same reference when the
- * bundle carries neither key (or the served value overrides both).
+ * `description` against `reports.<name>.label` / `.description`, and each
+ * joined block's against `reports.<name>.blocks.<block_name>.label` /
+ * `.description`. The input document is not mutated, and it comes back as
+ * the same reference when the bundle carries none of those keys (or the
+ * served values override them).
  *
  * These are the two strings the console lists a report by on the app's report
  * index, and the report page's heading. Registered in
  * {@link METADATA_DOCUMENT_TRANSLATORS}, so the REST boundary localizes every
  * served report (`GET /meta/report`, list and item) with nothing else to
- * remember.
+ * remember. A joined report's block `label` / `description` are the heading
+ * and caption its renderer draws above each block, read off the served
+ * document as is — so serving them translated here is the whole wiring.
  *
  * ## The catalog loses to an explicit override — ADR-0029 D9.2a
  *
@@ -2292,11 +2358,13 @@ export function translateReport<T extends ReportLike>(
   const description = valueOverridesPackagedBase(base, 'description', doc.description)
     ? undefined
     : lookupReportAttr(bundle, name, 'description', opts);
-  if (label === undefined && description === undefined) return doc;
+  const blocks = translateReportBlocks(doc.blocks, bundle, name, base, opts);
+  if (label === undefined && description === undefined && blocks === undefined) return doc;
   return {
     ...doc,
     ...(label !== undefined ? { label } : {}),
     ...(description !== undefined ? { description } : {}),
+    ...(blocks !== undefined ? { blocks } : {}),
   };
 }
 
@@ -3233,6 +3301,8 @@ export interface ObjectFieldLike {
   name?: string;
   label?: string;
   description?: string;
+  /** `FieldSchema.inlineTitle` — the inline child grid's heading on the parent's form. */
+  inlineTitle?: string;
   options?: Array<{ label?: string; value: string | number | boolean }>;
   [key: string]: any;
 }
@@ -3256,7 +3326,7 @@ function lookupObjectFieldAttr(
   bundle: TranslationBundle | undefined,
   objectName: string,
   fieldName: string,
-  attr: 'label' | 'help' | 'description',
+  attr: 'label' | 'help' | 'description' | 'inlineTitle',
   opts?: ResolveOptions,
 ): string | undefined {
   if (!bundle) return undefined;
@@ -3833,6 +3903,15 @@ function translateObjectListViews(
  * the base does not declare was authored after the fact, and its description
  * counts as diverged; no base supplied means nothing is inferred and the
  * catalog applies.
+ *
+ * ## A field's `inlineTitle` — the inline child grid's heading
+ *
+ * `objects.<child>.fields.<field>.inlineTitle` overlays the field's own
+ * `inlineTitle` under that same rule. The field sits on the CHILD object, but
+ * its heading is drawn on the PARENT's form: the console's inline-subform pass
+ * copies the served child field's `inlineTitle` as is, so serving it
+ * translated here is the whole wiring. An authored heading with no entry keeps
+ * its text; the child's plural label is never swapped in for it.
  */
 export function translateObject<T extends ObjectLike>(
   doc: T,
@@ -3874,6 +3953,14 @@ export function translateObject<T extends ObjectLike>(
       const translatedDescription = lookupObjectFieldAttr(bundle, objectName, name, 'help', opts);
       if (translatedDescription) next.description = translatedDescription;
     }
+    // The inline child grid's heading, under the same divergence rule. The
+    // console's inline-subform pass copies the served value onto the parent's
+    // form, so this is the one place it is localized. An untranslated heading
+    // keeps its authored text — never the child's plural label in its place.
+    if (!valueOverridesPackagedBase(packagedObjectField(packagedObject, name), 'inlineTitle', def.inlineTitle)) {
+      const translatedInlineTitle = lookupObjectFieldAttr(bundle, objectName, name, 'inlineTitle', opts);
+      if (translatedInlineTitle) next.inlineTitle = translatedInlineTitle;
+    }
     if (Array.isArray(def.options)) {
       // A picklist-bound field is served with its list's options resolved
       // onto it (`PicklistServedFieldSchema`), and INHERITS the list's option
diff --git a/packages/spec/src/system/translation.zod.ts b/packages/spec/src/system/translation.zod.ts
index 525953111fe..d8bd010ad95 100644
--- a/packages/spec/src/system/translation.zod.ts
+++ b/packages/spec/src/system/translation.zod.ts
@@ -125,6 +125,21 @@ export const FieldTranslationSchema = lazySchema(() => strictObject({
   help: z.string().optional().describe('Translated help text'),
   placeholder: z.string().optional().describe('Translated placeholder text for form inputs'),
   options: z.record(z.string(), z.string()).optional().describe('Option value to translated label map'),
+  /**
+   * The field's own `inlineTitle` — the heading of the inline child grid a
+   * `master_detail` / `lookup` field with `inlineEdit` draws on its PARENT's
+   * form. The field lives on the child object, so the address is the child's:
+   * `objects.<child>.fields.<field>.inlineTitle`. Overlaid by
+   * `translateObject` on the served child object, which is what the console's
+   * inline-subform pass copies the heading from.
+   *
+   * No fallback to the child object's translated plural label: an authored
+   * `inlineTitle` with no entry here keeps its authored text, because a
+   * bundle translates an attribute and never swaps another attribute in over
+   * authored text. An absent `inlineTitle` already renders the child's
+   * (translated) label.
+   */
+  inlineTitle: z.string().optional().describe("Translated inline master-detail grid title — overlays the field's own `inlineTitle`"),
 }).describe('Translation data for a single field'));
 
 export type FieldTranslation = z.input<typeof FieldTranslationSchema>;
@@ -1140,6 +1155,10 @@ const appTranslationDataShape = () => ({
    *
    *   reports.<name>.label        → the report's own `label`
    *   reports.<name>.description  → the report's own `description`
+   *   reports.<name>.blocks.<block_name>.label / .description
+   *                               → a joined report block's own `label` /
+   *                                 `description`, keyed by the block's
+   *                                 required `name`
    *
    * The two strings the console's report index lists each report by, and the
    * report page's heading. Overlaid by `translateReport` (`i18n-resolver.ts`)
@@ -1148,9 +1167,9 @@ const appTranslationDataShape = () => ({
    * O), so, as on a dashboard, the catalog yields to a label or description
    * an org has re-authored on top of the packaged report (ADR-0029 D9.2a).
    *
-   * The face stops at those two strings. A report's selection (`dataset`,
-   * `rows`, `columns`, `values`) is machine names whose display copy is the
-   * dataset's, translated at `datasets.<dataset_name>`.
+   * The face stops at those strings. A report's selection (`dataset`,
+   * `rows`, `columns`, `values`), and a block's, is machine names whose
+   * display copy is the dataset's, translated at `datasets.<dataset_name>`.
    *
    * ⚠️ `label` and `description` are `I18nLabelSchema` at the authoring site,
    * so a report's copy may already be an inline `{ en, 'zh-CN' }` map.
@@ -1164,6 +1183,22 @@ const appTranslationDataShape = () => ({
   }, {
     label: z.string().optional().describe("Translated report label — overlays the report's own `label`"),
     description: z.string().optional().describe("Translated report description — overlays the report's own `description`"),
+    /**
+     * A joined report's block copy, keyed by the block's `name`
+     * (`JoinedReportBlockSchema.name`, required). The heading and caption the
+     * joined renderer draws above each block; without this slot a localized
+     * report showed a translated title over block headings left in the
+     * authoring language. Overlaid by `translateReport`, block by block, under
+     * the same packaged-base rule as the report's own two strings.
+     */
+    blocks: z.record(z.string(), strictObject({
+      surface: 'this joined report block translation',
+      history: TRANSLATION_HISTORY,
+      aliases: { name: 'label', title: 'label', heading: 'label' },
+    }, {
+      label: z.string().optional().describe("Translated block label — overlays the joined report block's own `label`"),
+      description: z.string().optional().describe("Translated block description — overlays the joined report block's own `description`"),
+    })).optional().describe('Joined report block translations keyed by block name'),
   })).optional().describe('Report translations keyed by report name'),
 
   /**