Link DataGrid's Together

Question

I have 2 datagrids on 2 different forms bound to 2 different SQL tables.  On the 1st datagrid, I have a DataGridViewButtonColumn called Details.  Both DataGrids have a TimeEntryID column in common.  I would like to be able to click on the Details button in the 1st DataGrid and be able to link the TimeEntryID column to the TimeEntryID column in the 2nd DataGrid.  How can I do this?  I am relatively new to VB.NET.
Thanks!