Chen,

>>Without NavControl:

This is correct, because if you haven't specified the grid as your navigation control, then the navigation events don't get fired properly.

>>With NavControl:

In this scenario, the navigation events are firing properly in the parent, and the child is receiving and responding to events. In order for a grandchild object to respond, you need to put code in the HookParentNavigated event of the child object that will in turn fire an event in the grandchild object.

Regards,