Nested GridView with Paging in ASP.Net

I used your code to set up a datagrid with a child datagrid

http://www.aspsnippets.com/Articles/ASPNet-Nested-GridViews-GridView-inside-GridView-with-Expand-and-Collapse-feature.aspx

I then added pagination to the child grid..which seemed to work until you click on a page..

I have code for handling the PageIndexChanging for the parent grid. Do I need a seperate pahe handling sub for the child?