Define dependency between nodes in WPF TreeviewItem

Hi Folks.

I am newbie to WPF.Working on treeview with MVVM pattern.Currently I am binding xml data to Treeview ItemsSource.(Treeview with checkbox).

How can I define dependency between nodes like 

A
---B
---C
---D
E
---F
---G
---H
I
---J

If I select B treeviewitem then F should also get auto selected.How and where to define the relationship between nodes. and how to implement using MVVM pattern