I need some help and advice on something;

I have 3 grids, one grid is a record where the user enters control information, and from here a header record in a grid and a detail record in a grid are refreshed to show to the user. Based on what is entered into the combobox in the first grid, data for that specific value in the combobox should show up in the other 2 grids. This works, the problem is after the combox is selected on the click item the other 2 grids don't refresh correctly. I have to move over and select the record for the click to work. I want the refresh to work immediately after the item in the combobox click is selected. I inserted the combobox after the grid was created, so I assume the properties of the combobox overwrote the grid column properties so the click doesn't work correctly. This isn't in a class, but a regular form. I am also using a regular grid, this isn't a flexgrid. How can I get the click to work correctly in the combobox and refresh the other 2 grids correctly? What would everyone recommend? Thanks for any ideas or recommendations.
I can provide more information if needed.
thanks,
Alp