DataGrid Column Bind With Different Table(Nested)

Question

  hi,
   I have to using WCF ria service,My stored procedure  retrive the Three Different table as Result,I want to bind that result to my datagrid,The result will be display as nested(like grouping).I know the Grouping on one column in datagrid.How to return the reault of store procedure to silverlight page(for bind Datagrid).My datagrid will be show like below image..