diff --git a/src/Nodes/NodeTrait.php b/src/Nodes/NodeTrait.php
index 9616a4d..5598877 100644
--- a/src/Nodes/NodeTrait.php
+++ b/src/Nodes/NodeTrait.php
@@ -370,7 +370,7 @@ public function createNode($originalNode, $tagName)
      *
      * @return bool
      */
-    public function hasAncestorTag($tagName, $maxDepth = 3, callable $filterFn = null)
+    public function hasAncestorTag($tagName, $maxDepth = 3, ?callable $filterFn = null)
     {
         $depth = 0;
         $node = $this;