Member Nodes (All)

If the selected part is a Group, this collection includes all Nodes whose parent is your selected Group, and all of their child nodes, recursively.  For example, Group Psi is the only immediate child member Node of Group Chi.  However, Node F is a member of Group Omega, which in turn is a member of Group Psi. Thus, clicking on Chi will result in Node F being highlighted as well.

The logic to highlight the appropriate Nodes is in the RecursiveChildren method.  Each successive child relationship increases the Highlight property value.