diff --git a/Stdlib/Tree/BinarySearchTree.php b/Stdlib/Tree/BinarySearchTree.php
index 885ba1123..729cae455 100644
--- a/Stdlib/Tree/BinarySearchTree.php
+++ b/Stdlib/Tree/BinarySearchTree.php
@@ -257,7 +257,9 @@ class BinarySearchTree
                 }
             }
 
-            $temp->parent = $node?->parent;
+            if ($temp !== null) {
+                $temp->parent = $node->parent;
+            }
 
             $node = null;
 
@@ -278,7 +280,9 @@ class BinarySearchTree
                 }
             }
 
-            $temp->parent = $node?->parent;
+            if ($temp !== null) {
+                $temp->parent = $node->parent;
+            }
 
             $node = null;