diff -rupN VTK-9.2.6/Utilities/octree/octree/octree_node.txx VTK-9.2.6-new/Utilities/octree/octree/octree_node.txx
--- VTK-9.2.6/Utilities/octree/octree/octree_node.txx	2023-02-15 05:03:53.000000000 +0100
+++ VTK-9.2.6-new/Utilities/octree/octree/octree_node.txx	2025-01-24 14:12:16.855255487 +0100
@@ -207,7 +207,7 @@ const octree_node<T_, d_, A_>& octree_no
   {
     throw std::domain_error("Attempt to access children of an octree leaf node.");
   }
-  return this->_M_chilren[child];
+  return this->m_children[child];
 }
 
 /**\brief Return a reference to a child node.