diff --git a/packages/visx-event/src/typeGuards.ts b/packages/visx-event/src/typeGuards.ts
index 9349f141d3..24320328f3 100644
--- a/packages/visx-event/src/typeGuards.ts
+++ b/packages/visx-event/src/typeGuards.ts
@@ -28,10 +28,19 @@ export function isMouseEvent(event?: EventType): event is MouseEvent {
   return !!event && 'clientX' in event;
 }
 
-// functional definition of event
-export function isEvent(event?: EventType | Element): event is EventType {
+function isNativeEvent(event: any): event is Event {
+  return event && typeof event === 'object' && 'target' in event && 'currentTarget' in event;
+}
+
+function isReactSyntheticEvent(event: any): event is React.SyntheticEvent {
   return (
-    !!event &&
-    (event instanceof Event || ('nativeEvent' in event && event.nativeEvent instanceof Event))
+    event &&
+    typeof event === 'object' &&
+    'nativeEvent' in event &&
+    isNativeEvent((event as React.SyntheticEvent).nativeEvent)
   );
 }
+
+export function isEvent(event?: EventType | Element): event is EventType {
+  return !!event && (isNativeEvent(event) || isReactSyntheticEvent(event));
+}
diff --git a/packages/visx-xychart/src/components/Tooltip.tsx b/packages/visx-xychart/src/components/Tooltip.tsx
index f5a763d6a7..59fcdb513d 100644
--- a/packages/visx-xychart/src/components/Tooltip.tsx
+++ b/packages/visx-xychart/src/components/Tooltip.tsx
@@ -93,6 +93,22 @@ function defaultRenderGlyph<Datum extends object>(props: RenderTooltipGlyphProps
   return <DefaultGlyph {...props} />;
 }
 
+function getIframeOffsets(target) {
+  let offsetX = 0;
+  let offsetY = 0;
+  let currentWindow = target.ownerDocument.defaultView;
+
+  while (currentWindow && currentWindow.frameElement) {
+    const frameElement = currentWindow.frameElement;
+    const frameRect = frameElement.getBoundingClientRect();
+    offsetX += frameRect.left;
+    offsetY += frameRect.top;
+    currentWindow = currentWindow.parent;
+  }
+
+  return { x: offsetX, y: offsetY };
+}
+
 function TooltipInner<Datum extends object>({
   debounce,
   detectBounds,
@@ -132,15 +148,46 @@ function TooltipInner<Datum extends object>({
     zIndex,
   });
 
+  function getIframeOffsets(target) {
+    let offsetX = 0;
+    let offsetY = 0;
+    let currentWindow = target.ownerDocument.defaultView;
+
+    while (currentWindow && currentWindow.frameElement) {
+      const frameElement = currentWindow.frameElement;
+      const frameRect = frameElement.getBoundingClientRect();
+      offsetX += frameRect.left;
+      offsetY += frameRect.top;
+      currentWindow = currentWindow.parent;
+    }
+
+    return { x: offsetX, y: offsetY };
+  }
+
   // To correctly position itself in a Portal, the tooltip must know its container bounds
   // this is done by rendering an invisible node whose ref can be used to find its parentElement
   const setContainerRef = useCallback(
     (ownRef: HTMLElement | SVGElement | null) => {
-      containerRef(ownRef?.parentElement ?? null);
+      if (ownRef && ownRef.parentElement instanceof Element) {
+        const iframeOffsets = getIframeOffsets(ownRef);
+        const parentRect = ownRef.parentElement.getBoundingClientRect();
+        const adjustedContainer = {
+          ...ownRef.parentElement,
+          getBoundingClientRect: () => ({
+            ...parentRect,
+            x: parentRect.x + iframeOffsets.x,
+            y: parentRect.y + iframeOffsets.y,
+            left: parentRect.left + iframeOffsets.x,
+            top: parentRect.top + iframeOffsets.y,
+          }),
+        };
+        containerRef(adjustedContainer);
+      } else {
+        containerRef(null);
+      }
     },
     [containerRef],
   );
-
   const tooltipContent = tooltipContext?.tooltipOpen
     ? renderTooltip({ ...tooltipContext, colorScale })
     : null;
@@ -301,10 +348,9 @@ function TooltipInner<Datum extends object>({
               </svg>
             </TooltipInPortal>
           )}
-          {glyphProps.map(({ x, y, ...props }, i) => (
-            // We render glyps in a portal so that they can overflow the container if necessary
+          {glyphProps.map(({ key, x, y, ...props }) => (
             <TooltipInPortal
-              key={i}
+              key={key}
               className="visx-tooltip-glyph"
               left={x}
               top={y}