diff --git a/src/renderer/src/components/sidebar/WorktreeCard.tsx b/src/renderer/src/components/sidebar/WorktreeCard.tsx
index bbcc35e750e..ea543a0966f 100644
--- a/src/renderer/src/components/sidebar/WorktreeCard.tsx
+++ b/src/renderer/src/components/sidebar/WorktreeCard.tsx
@@ -35,6 +35,7 @@ const WorktreeCard = React.memo(function WorktreeCard({
   contentIndent = 0,
   flushSurface = false,
   lineageChildCount = 0,
+  lineageChildWorktreeIds,
   lineageCollapsed = false,
   lineageChildren,
   lineageChildrenStyle,
@@ -71,6 +72,7 @@ const WorktreeCard = React.memo(function WorktreeCard({
     contentIndent,
     flushSurface,
     lineageChildCount,
+    lineageChildWorktreeIds,
     lineageCollapsed,
     lineageChildren,
     lineageChildrenStyle,
diff --git a/src/renderer/src/components/sidebar/WorktreeLineageToggle.tsx b/src/renderer/src/components/sidebar/WorktreeLineageToggle.tsx
new file mode 100644
index 00000000000..69f215f8604
--- /dev/null
+++ b/src/renderer/src/components/sidebar/WorktreeLineageToggle.tsx
@@ -0,0 +1,130 @@
+import React, { useId } from 'react'
+import { ChevronDown, Workflow } from 'lucide-react'
+import { Button } from '@/components/ui/button'
+import { Tooltip, TooltipContent, TooltipTrigger } from '@/components/ui/tooltip'
+import { translate } from '@/i18n/i18n'
+import { getWorktreeStatusLabel, type WorktreeStatus } from '@/lib/worktree-status'
+import { cn } from '@/lib/utils'
+import StatusIndicator from './StatusIndicator'
+import { useWorktreeActivityStatuses } from './use-worktree-activity-statuses'
+
+const EMPTY_CHILD_IDS: readonly string[] = []
+const STATUS_ORDER: readonly WorktreeStatus[] = [
+  'permission',
+  'failed',
+  'unconfirmed',
+  'working',
+  'monitoring',
+  'interrupted',
+  'done',
+  'active'
+]
+
+export function WorktreeLineageToggle({
+  childWorktreeIds = EMPTY_CHILD_IDS,
+  collapsed,
+  ariaLabel,
+  count,
+  newCardStyle,
+  onToggle
+}: {
+  childWorktreeIds?: readonly string[]
+  collapsed: boolean
+  ariaLabel: string
+  count: number
+  newCardStyle: boolean
+  onToggle?: React.MouseEventHandler<HTMLButtonElement>
+}): React.JSX.Element {
+  const descriptionId = useId()
+  const statuses = useWorktreeActivityStatuses(childWorktreeIds)
+  const counts = new Map<WorktreeStatus, number>()
+  for (const status of statuses.values()) {
+    counts.set(status, (counts.get(status) ?? 0) + 1)
+  }
+  const summary = STATUS_ORDER.filter((status) => counts.has(status))
+  const description = summary
+    .map((status) => `${counts.get(status)} ${getWorktreeStatusLabel(status)}`)
+    .join(', ')
+
+  return (
+    <div
+      className={cn(
+        '@container relative mt-1 flex min-w-0 justify-start',
+        !newCardStyle && '-ml-1'
+      )}
+    >
+      <Tooltip>
+        <TooltipTrigger asChild>
+          <Button
+            type="button"
+            variant="outline"
+            size="chip"
+            className="relative z-10 h-auto min-h-4.5 max-w-full"
+            aria-label={ariaLabel}
+            aria-describedby={description ? descriptionId : undefined}
+            aria-expanded={!collapsed}
+            onClick={onToggle}
+          >
+            <span className="inline-flex min-w-0 flex-wrap items-center gap-1 px-1 py-0.5">
+              <span className="inline-flex shrink-0 items-center gap-1">
+                <Workflow className="size-2.5 shrink-0" />
+                <span className="tabular-nums">{count}</span>
+              </span>
+              <span className={cn('truncate', summary.length > 0 && 'hidden @min-[13rem]:block')}>
+                {count === 1
+                  ? translate('auto.components.sidebar.WorktreeList.0c6ee14f23', 'child')
+                  : translate('auto.components.sidebar.WorktreeList.045a8aed48', 'children')}
+              </span>
+              <span className="inline-flex min-w-0 max-w-full items-center gap-0.5">
+                {summary.length > 0 ? (
+                  <span className="inline-flex min-w-0 flex-wrap items-center gap-1 border-l border-border pl-1">
+                    {summary.map((status) => (
+                      <span
+                        key={status}
+                        className="inline-flex shrink-0 items-center gap-0.5 tabular-nums"
+                        data-child-worktree-status={status}
+                        aria-hidden="true"
+                      >
+                        {status === 'working' ? (
+                          <span className="inline-flex size-3 shrink-0 items-center justify-center">
+                            <span className="size-2 rounded-full bg-agent-working" />
+                          </span>
+                        ) : (
+                          <StatusIndicator status={status} showTooltip={false} />
+                        )}
+                        {counts.get(status)}
+                      </span>
+                    ))}
+                  </span>
+                ) : null}
+                <ChevronDown
+                  className={cn(
+                    'size-2.5 shrink-0 transition-transform',
+                    collapsed && '-rotate-90'
+                  )}
+                />
+              </span>
+            </span>
+          </Button>
+        </TooltipTrigger>
+        <TooltipContent side="right" sideOffset={8}>
+          {collapsed
+            ? translate(
+                'auto.components.sidebar.WorktreeCard.showChildWorktrees',
+                'Show children worktrees'
+              )
+            : translate(
+                'auto.components.sidebar.WorktreeCard.hideChildWorktrees',
+                'Hide children worktrees'
+              )}
+          {description ? <div>{description}</div> : null}
+        </TooltipContent>
+      </Tooltip>
+      {description ? (
+        <span id={descriptionId} className="sr-only">
+          {description}
+        </span>
+      ) : null}
+    </div>
+  )
+}
diff --git a/src/renderer/src/components/sidebar/worktree-card-model.ts b/src/renderer/src/components/sidebar/worktree-card-model.ts
index 43aa0fad75e..282521d911d 100644
--- a/src/renderer/src/components/sidebar/worktree-card-model.ts
+++ b/src/renderer/src/components/sidebar/worktree-card-model.ts
@@ -33,6 +33,7 @@ export type WorktreeCardProps = {
   contentIndent?: number
   flushSurface?: boolean
   lineageChildCount?: number
+  lineageChildWorktreeIds?: readonly string[]
   lineageCollapsed?: boolean
   lineageChildren?: React.ReactNode
   lineageChildrenStyle?: React.CSSProperties
diff --git a/src/renderer/src/components/sidebar/worktree-card-secondary-rows.tsx b/src/renderer/src/components/sidebar/worktree-card-secondary-rows.tsx
index c8188596f14..6062821252d 100644
--- a/src/renderer/src/components/sidebar/worktree-card-secondary-rows.tsx
+++ b/src/renderer/src/components/sidebar/worktree-card-secondary-rows.tsx
@@ -1,12 +1,11 @@
 import React from 'react'
-import { AlertTriangle, ChevronDown, Workflow } from 'lucide-react'
+import { AlertTriangle } from 'lucide-react'
 
-import { Button } from '@/components/ui/button'
 import { Tooltip, TooltipContent, TooltipTrigger } from '@/components/ui/tooltip'
 import { translate } from '@/i18n/i18n'
-import { cn } from '@/lib/utils'
 import { LinearAgentSkillSetupPrompt } from './LinearAgentSkillSetupPrompt'
 import WorktreeCardAgents from './WorktreeCardAgents'
+import { WorktreeLineageToggle } from './WorktreeLineageToggle'
 import type { WorktreeCardPresentation } from './worktree-card-presentation'
 import type { WorktreeCardController } from './use-worktree-card-controller'
 
@@ -24,6 +23,7 @@ export function WorktreeCardSecondaryRows({
     isActive,
     newCardStyle,
     lineageCollapsed,
+    lineageChildWorktreeIds,
     onLineageToggle,
     remoteBranchConflict,
     showInlineAgentList,
@@ -31,7 +31,7 @@ export function WorktreeCardSecondaryRows({
     compactInlineAgentRows,
     showLineageChildChip,
     lineageChildAriaLabel,
-    childWorkspaceShortLabel,
+    lineageChildCount,
     isDeleting
   } = card
   const { hasMetaRow } = presentation
@@ -94,43 +94,14 @@ export function WorktreeCardSecondaryRows({
       )}
 
       {showLineageChildChip && (
-        <div
-          className={cn('relative mt-1 flex min-w-0 justify-start', !newCardStyle && '-ml-1')}
-          style={{
-            color: 'color-mix(in srgb, var(--muted-foreground) 42%, var(--worktree-sidebar))'
-          }}
-        >
-          <Tooltip>
-            <TooltipTrigger asChild>
-              <Button
-                type="button"
-                variant="ghost"
-                size="xs"
-                className="relative z-10 h-[18px] max-w-[8rem] gap-1 rounded-md border border-worktree-sidebar-border bg-worktree-sidebar px-1.5 text-[10px] font-medium leading-none text-muted-foreground shadow-none hover:bg-worktree-sidebar-accent hover:text-foreground focus-visible:ring-1 focus-visible:ring-worktree-sidebar-ring"
-                aria-label={lineageChildAriaLabel}
-                aria-expanded={!lineageCollapsed}
-                onClick={onLineageToggle}
-              >
-                <Workflow className="size-2.5" />
-                <span className="truncate">{childWorkspaceShortLabel}</span>
-                <ChevronDown
-                  className={cn('size-2.5 transition-transform', lineageCollapsed && '-rotate-90')}
-                />
-              </Button>
-            </TooltipTrigger>
-            <TooltipContent side="right" sideOffset={8}>
-              {lineageCollapsed
-                ? translate(
-                    'auto.components.sidebar.WorktreeCard.8cb634cda6',
-                    'Show child workspaces'
-                  )
-                : translate(
-                    'auto.components.sidebar.WorktreeCard.57eaa61b55',
-                    'Hide child workspaces'
-                  )}
-            </TooltipContent>
-          </Tooltip>
-        </div>
+        <WorktreeLineageToggle
+          childWorktreeIds={lineageChildWorktreeIds}
+          collapsed={lineageCollapsed}
+          ariaLabel={lineageChildAriaLabel}
+          count={lineageChildCount}
+          newCardStyle={newCardStyle}
+          onToggle={onLineageToggle}
+        />
       )}
     </>
   )
diff --git a/src/renderer/src/components/sidebar/worktree-list-groups-lineage-nesting.test.ts b/src/renderer/src/components/sidebar/worktree-list-groups-lineage-nesting.test.ts
index e0fc9f8873b..48284e03bfb 100644
--- a/src/renderer/src/components/sidebar/worktree-list-groups-lineage-nesting.test.ts
+++ b/src/renderer/src/components/sidebar/worktree-list-groups-lineage-nesting.test.ts
@@ -222,7 +222,11 @@ describe('buildRows workspace lineage nesting', () => {
       [secondChildId, 1],
       [childId, 1]
     ])
-    expect(items[0]).toMatchObject({ lineageChildCount: 2, lineageCollapsed: false })
+    expect(items[0]).toMatchObject({
+      lineageChildCount: 2,
+      lineageChildWorktreeIds: [secondChildId, childId],
+      lineageCollapsed: false
+    })
   })
 
   it('rejects stale resolved lineage after a parent instance is replaced', () => {
@@ -471,6 +475,7 @@ describe('buildRows workspace lineage nesting', () => {
       type: 'item',
       worktree: { id: parent.id },
       lineageChildCount: 1,
+      lineageChildWorktreeIds: [child.id],
       lineageCollapsed: true
     })
   })
diff --git a/src/renderer/src/components/sidebar/worktree-list/rows/item-row.tsx b/src/renderer/src/components/sidebar/worktree-list/rows/item-row.tsx
index 9540b9023ec..9e7be884547 100644
--- a/src/renderer/src/components/sidebar/worktree-list/rows/item-row.tsx
+++ b/src/renderer/src/components/sidebar/worktree-list/rows/item-row.tsx
@@ -204,6 +204,7 @@ export function renderWorktreeItemRow(
         inPinnedSection={itemRow.sectionKey === PINNED_GROUP_KEY}
         renameRowKey={itemRow.rowKey}
         lineageChildCount={itemRow.lineageChildCount}
+        lineageChildWorktreeIds={itemRow.lineageChildWorktreeIds}
         lineageCollapsed={itemRow.lineageCollapsed}
         lineageChildren={lineageChildren}
         lineageChildrenStyle={lineageChildrenStyle}
diff --git a/src/renderer/src/i18n/en-runtime-required.json b/src/renderer/src/i18n/en-runtime-required.json
index 75f112ba3a1..a35b10f3b3b 100644
--- a/src/renderer/src/i18n/en-runtime-required.json
+++ b/src/renderer/src/i18n/en-runtime-required.json
@@ -2156,6 +2156,8 @@
           "01f45d3d8a": "sidebar",
           "021538e1d1": "SSH disconnected",
           "1d66d84f0b": "string",
+          "57eaa61b55": "Hide child workspaces",
+          "8cb634cda6": "Show child workspaces",
           "93aebe4529": "Folder",
           "automationCreated": "Created by automation",
           "branchFolderPathIdentity": "Branch or folder path",
diff --git a/src/renderer/src/i18n/locales/en.json b/src/renderer/src/i18n/locales/en.json
index 0745ee9c113..689f564e4af 100644
--- a/src/renderer/src/i18n/locales/en.json
+++ b/src/renderer/src/i18n/locales/en.json
@@ -6101,7 +6101,9 @@
           "automationCreated": "Created by automation",
           "branchIdentity": "Branch",
           "branchFolderPathIdentity": "Branch or folder path",
-          "ef18787206": "Queued for deletion"
+          "ef18787206": "Queued for deletion",
+          "showChildWorktrees": "Show children worktrees",
+          "hideChildWorktrees": "Hide children worktrees"
         },
         "WorktreeCardAgents": {
           "1b0a156717": "Agents"
diff --git a/src/shared/sidebar-list/row-builders.ts b/src/shared/sidebar-list/row-builders.ts
index f92a12af757..646cecb2b01 100644
--- a/src/shared/sidebar-list/row-builders.ts
+++ b/src/shared/sidebar-list/row-builders.ts
@@ -77,9 +77,18 @@ export function appendWorktreeRows(
     hostContextLabelByWorktreeIdentity?: ReadonlyMap<string, string>
   }
 ): void {
-  const occurrences = getExpandedWorktreeOccurrences(
-    plan.bySection.get(options.sectionKey) ?? [],
-    (worktree) => options.collapsedGroups.has(getWorktreeLineageGroupKey(worktree))
+  const sectionOccurrences = plan.bySection.get(options.sectionKey) ?? []
+  // Keep disclosure membership available while child rows are collapsed.
+  const childIdsByParent = new Map<string, string[]>()
+  for (const occurrence of sectionOccurrences) {
+    if (occurrence.parent) {
+      const children = childIdsByParent.get(occurrence.parent.key) ?? []
+      children.push(occurrence.row.id)
+      childIdsByParent.set(occurrence.parent.key, children)
+    }
+  }
+  const occurrences = getExpandedWorktreeOccurrences(sectionOccurrences, (worktree) =>
+    options.collapsedGroups.has(getWorktreeLineageGroupKey(worktree))
   )
   for (const occurrence of occurrences) {
     const worktree = occurrence.row
@@ -94,6 +103,7 @@ export function appendWorktreeRows(
       groupDepth: options.groupDepth,
       isLastLineageChild: occurrence.isLastChild,
       lineageChildCount: occurrence.childCount,
+      lineageChildWorktreeIds: childIdsByParent.get(occurrence.key),
       showProjectName: occurrence.showProjectName,
       hostContextLabel:
         options.hostContextLabelByWorktreeIdentity?.get(getWorktreeHostIdentity(worktree)) ??
diff --git a/src/shared/sidebar-list/row-types.ts b/src/shared/sidebar-list/row-types.ts
index 9c58f04be2f..8a7c2f966c5 100644
--- a/src/shared/sidebar-list/row-types.ts
+++ b/src/shared/sidebar-list/row-types.ts
@@ -56,6 +56,7 @@ export type WorktreeRow = {
   groupDepth: number
   isLastLineageChild: boolean
   lineageChildCount: number
+  lineageChildWorktreeIds?: readonly string[]
   lineageGroupKey?: string
   lineageCollapsed?: boolean
   hostContextLabel?: string