diff --git a/codex-rs/tui/src/chatwidget/protocol.rs b/codex-rs/tui/src/chatwidget/protocol.rs
index 9d2920807..3682f245f 100644
--- a/codex-rs/tui/src/chatwidget/protocol.rs
+++ b/codex-rs/tui/src/chatwidget/protocol.rs
@@ -6,6 +6,15 @@ impl ChatWidget {
         notification: ServerNotification,
         replay_kind: Option<ReplayKind>,
     ) {
+        // Reject misrouted child updates before shared notification handling mutates parent state.
+        if let ServerNotification::McpServerStatusUpdated(notification) = &notification
+            && let (Some(notification_thread_id), Some(thread_id)) =
+                (notification.thread_id.as_deref(), self.thread_id())
+            && notification_thread_id != thread_id.to_string()
+        {
+            return;
+        }
+
         let from_replay = replay_kind.is_some();
         let is_resume_initial_replay =
             matches!(replay_kind, Some(ReplayKind::ResumeInitialMessages));
diff --git a/codex-rs/tui/src/chatwidget/tests/mcp_startup.rs b/codex-rs/tui/src/chatwidget/tests/mcp_startup.rs
index 8b0d5ca47..60efbe135 100644
--- a/codex-rs/tui/src/chatwidget/tests/mcp_startup.rs
+++ b/codex-rs/tui/src/chatwidget/tests/mcp_startup.rs
@@ -25,6 +25,47 @@ fn notify_mcp_status_error(chat: &mut ChatWidget, name: &str, error: &str) {
     );
 }
 
+#[tokio::test]
+async fn mcp_startup_ignores_status_for_other_thread() {
+    let (mut chat, mut rx, _op_rx) = make_chatwidget_manual(/*model_override*/ None).await;
+    chat.show_welcome_banner = false;
+    chat.set_mcp_startup_expected_servers(["sentry".to_string()]);
+    let parent_thread_id = ThreadId::new();
+    let child_thread_id = ThreadId::new();
+    chat.thread_id = Some(parent_thread_id);
+    chat.on_stream_error(
+        "Connection interrupted, retrying".to_string(),
+        /*additional_details*/ None,
+    );
+    let status_before = chat.status_state.current_status.clone();
+    let retry_status_header_before = chat.status_state.retry_status_header.clone();
+
+    for status in [
+        McpServerStartupState::Starting,
+        McpServerStartupState::Failed,
+    ] {
+        chat.handle_server_notification(
+            ServerNotification::McpServerStatusUpdated(McpServerStatusUpdatedNotification {
+                thread_id: Some(child_thread_id.to_string()),
+                name: "sentry".to_string(),
+                status,
+                error: matches!(status, McpServerStartupState::Failed)
+                    .then(|| "sentry is not logged in".to_string()),
+            }),
+            /*replay_kind*/ None,
+        );
+    }
+
+    assert!(drain_insert_history(&mut rx).is_empty());
+    assert!(!chat.bottom_pane.is_task_running());
+    assert!(chat.mcp_startup_status.is_none());
+    assert_eq!(chat.status_state.current_status, status_before);
+    assert_eq!(
+        chat.status_state.retry_status_header,
+        retry_status_header_before
+    );
+}
+
 #[tokio::test]
 async fn mcp_startup_dedupes_same_round_duplicate_failure_warning() {
     let (mut chat, mut rx, _op_rx) = make_chatwidget_manual(/*model_override*/ None).await;