In treeview, MyForm.MyTreeView.SelectedItem.Parent.Text (key or index) works
or
MyForm.MyTreeView.Nodes(MyForm.MyTreeView.SelectedItem).Parent.Text (etc)

I trick I use is to add (cocanenate?) the child key to the Parent or root key
Parent Key = [PARENT01]
Childkey=[PARENT01CHILD01] (get it?)
Then I can reference the parent with left(ChildKey,8) && PARENT01
or
Parentkey=Left(MyForm.MyTreeView.SelectedItem.Key,6)

You also have previous,next,child etc referencing.

I think it works the same for List.

>Anyone know how to determine the ListItem object that a ListSubItem belongs to?