Sheet window question

I want to force a MDI sheet window to come to the front and become the active sheet. I have tried to use SetFocus and BringToTop but they don't work.

I have a toolbar with First/Next/Prior/Last buttons and I want to be able to skip through the many sheet windows using the buttons.

Here is the First button code:

lw_sheet = gw_frame.GetFirstSheet()

If IsValid(lw_sheet) Then

   ???

End If