diff --git a/src/useEscKeyDown.ts b/src/useEscKeyDown.ts
index 90e31c6..31b2cb9 100644
--- a/src/useEscKeyDown.ts
+++ b/src/useEscKeyDown.ts
@@ -24,6 +24,10 @@ export default function useEscKeyDown(open: boolean, onEsc?: EscCallback) {
   }, [open, id]);
 
   useEffect(() => {
+    if (open && !stack.includes(id)) {
+      stack.push(id);
+    }
+
     if (!open) {
       return;
     }
diff --git a/tests/index.test.tsx b/tests/index.test.tsx
index f95eeba..db50b20 100644
--- a/tests/index.test.tsx
+++ b/tests/index.test.tsx
@@ -381,5 +381,49 @@ describe('Portal', () => {
       unmount();
       expect(stack).toHaveLength(0);
     });
+
+    it('onEsc should treat first mounted portal as top in StrictMode', () => {
+      const onEsc = jest.fn();
+    
+      const Demo = ({ visible }: { visible: boolean }) =>
+        visible ? (
+          <Portal open onEsc={onEsc}>
+            <div />
+          </Portal>
+        ) : null;
+    
+      render(<Demo visible />, { wrapper: React.StrictMode });
+    
+      expect(stack).toHaveLength(1);
+    
+      fireEvent.keyDown(window, { key: 'Escape' });
+    
+      expect(onEsc).toHaveBeenCalledWith(expect.objectContaining({ top: true }));
+    });
+
+    it('nested portals should trigger in correct order', () => {
+      const onEsc = jest.fn();
+      const onEsc2 = jest.fn();
+      const onEsc3 = jest.fn();
+
+      render(
+        <Portal open onEsc={onEsc}>
+          <div />
+          <Portal open onEsc={onEsc2}>
+            <div />
+            <Portal open onEsc={onEsc3}>
+              <div />
+            </Portal>
+          </Portal>
+        </Portal>
+      );
+
+      fireEvent.keyDown(window, { key: 'Escape' });
+
+      expect(onEsc).toHaveBeenCalledWith(expect.objectContaining({ top: false }));
+      expect(onEsc2).toHaveBeenCalledWith(expect.objectContaining({ top: false }));
+      expect(onEsc3).toHaveBeenCalledWith(expect.objectContaining({ top: true }));
+    });
+    
   });
 });