diff --git a/moli-protocol-server/src/protocol_server/tests/cdp_dynamic_page/auxiliary_page_identity.rs b/moli-protocol-server/src/protocol_server/tests/cdp_dynamic_page/auxiliary_page_identity.rs
index e8af315407..d6c2d510d6 100644
--- a/moli-protocol-server/src/protocol_server/tests/cdp_dynamic_page/auxiliary_page_identity.rs
+++ b/moli-protocol-server/src/protocol_server/tests/cdp_dynamic_page/auxiliary_page_identity.rs
@@ -999,6 +999,29 @@ async fn auxiliary_cross_origin_functions_and_descriptors_use_each_accessing_rea
     abort_test_cdp_server(server).await;
 }
 
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn auxiliary_page_adoption_preserves_native_node_and_owner_document_identity() {
+    let (addr, server) = spawn_test_protocol_server().await;
+    let (mut browser, _) =
+        connect_async(format!("ws://{addr}/devtools/browser/{DEFAULT_BROWSER_ID}"))
+            .await
+            .unwrap();
+    let opener_id = create_dynamic_target(&mut browser, 1).await;
+    let mut opener = connect_dynamic_page(addr, &opener_id).await;
+    let (_, _child) = open_auxiliary(addr, &mut opener, "").await;
+    assert_eq!(evaluate_window_name_probe(&mut opener, 2, r#"(()=>{
+        window.div=document.createElement('div');
+        window.span=document.createElement('span');div.append(span);
+        p.document.body.append(div);
+        return [div.ownerDocument===p.document,span.ownerDocument===p.document,p.document.body.firstChild===div,div.ownerDocument===document,div.ownerDocument.defaultView===p,p.document.defaultView===p];
+    })()"#).await, json!([true,true,true,false,true,true]));
+    assert_eq!(evaluate_window_name_probe(&mut opener, 3, r#"(()=>{
+        document.body.append(div);
+        return [div.ownerDocument===document,span.ownerDocument===document,document.body.lastChild===div];
+    })()"#).await, json!([true,true,true]));
+    abort_test_cdp_server(server).await;
+}
+
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn initial_same_origin_popup_commit_preserves_window_and_replaces_document() {
     let (fixture_addr, _fixture) = spawn_dedicated_fixture_server(
diff --git a/moli-renderer-v8/src/native_bridge/bridge/wrappers.rs b/moli-renderer-v8/src/native_bridge/bridge/wrappers.rs
index e58a220328..3500ed64cb 100644
--- a/moli-renderer-v8/src/native_bridge/bridge/wrappers.rs
+++ b/moli-renderer-v8/src/native_bridge/bridge/wrappers.rs
@@ -49,6 +49,20 @@ impl NativeDomBridge {
         host_ptr: *mut JsContextHost,
         handle: BridgeHandle,
     ) -> Option<v8::Local<'s, v8::Object>> {
+        if crate::util::context_host_ptr_from_context_slot(scope.get_current_context())
+            .is_some_and(|current| current != host_ptr)
+        {
+            // Reflector IDs are local to a DOM bridge. Related Pages share
+            // an isolate, but must never consult one another's wrapper cache.
+            let host = unsafe { &*host_ptr };
+            let dispatch_scope = crate::native_bridge::OwnerDispatchScope::Top;
+            let owner = host.current_window_execution_context_owner(dispatch_scope)?;
+            let context = host
+                .window_execution_context(scope, owner, dispatch_scope)?
+                .1;
+            let scope = &mut v8::ContextScope::new(scope, context);
+            return self.wrap_bridge_handle(scope, host_ptr, handle);
+        }
         let reflector_id = self.identity.reflector_id(&handle);
         if let Some(wrapper) = self.identity.cached_wrapper(scope, reflector_id) {
             return Some(wrapper);
diff --git a/moli-renderer-v8/src/native_bridge/helpers/identity.rs b/moli-renderer-v8/src/native_bridge/helpers/identity.rs
index 1f160120b8..cdbb01ac50 100644
--- a/moli-renderer-v8/src/native_bridge/helpers/identity.rs
+++ b/moli-renderer-v8/src/native_bridge/helpers/identity.rs
@@ -1,5 +1,5 @@
 use super::super::{BridgeHandle, JsContextHost, ReflectorId};
-use crate::util::context_host_ptr_from_global_bridge;
+use crate::util::{context_host_ptr_from_context_slot, context_host_ptr_from_global_bridge};
 use anyhow::{Context, bail, ensure};
 
 fn object_reflector_id(
@@ -32,7 +32,12 @@ pub(in crate::native_bridge) fn bridge_handle_from_object(
     scope: &mut v8::PinScope<'_, '_>,
     object: v8::Local<'_, v8::Object>,
 ) -> anyhow::Result<(*mut JsContextHost, BridgeHandle)> {
-    let runtime_ptr = context_host_ptr_from_global_bridge(scope)
+    // Related Pages share an isolate, but reflector IDs belong to the
+    // wrapper's original DOM bridge rather than the calling Window's bridge.
+    let runtime_ptr = object
+        .get_creation_context(scope)
+        .and_then(context_host_ptr_from_context_slot)
+        .or_else(|| context_host_ptr_from_global_bridge(scope))
         .context("current context has no JsContextHost")?;
     let reflector_id = object_reflector_id(scope, object)?;
     let handle = unsafe { &*runtime_ptr }
diff --git a/moli-renderer-v8/src/native_bridge/node.rs b/moli-renderer-v8/src/native_bridge/node.rs
index fe21bfc4f6..195f07ccbb 100644
--- a/moli-renderer-v8/src/native_bridge/node.rs
+++ b/moli-renderer-v8/src/native_bridge/node.rs
@@ -1216,6 +1216,12 @@ pub(crate) fn node_runtime_and_handle_from_object(
     scope: &mut v8::PinScope<'_, '_>,
     object: v8::Local<'_, v8::Object>,
 ) -> anyhow::Result<(*mut JsContextHost, DomHandle)> {
+    let object = v8::Local::new(scope, object);
+    if let Some(delegate) =
+        crate::util::get_private_object(scope, object, super::document::DETACHED_LIVE_DELEGATE_SLOT)
+    {
+        return node_runtime_and_handle_from_object(scope, delegate);
+    }
     let (runtime_ptr, handle) = super::bridge_handle_from_object(scope, object)
         .context("failed to resolve Node wrapper")?;
     match handle {