Button to scroll MDI Parent Form

Question

I am working on a touch screen application and I am trying to add a button(s) that function as  pageup/pagedown on a MDI Parent form with the child forms as the items to scroll.

I've spent entirely way too much time scouring the internet for a solution to this. I've tried multiple items that I thought would be the answer to no avail.

I really thought that this would be the answer:

SendMessage(this.Handle, WM_VSCROLL, (IntPtr) SB_PAGEDOWN, IntPtr.Zero);

I know I'm close, but then again, I could be way off!

Ideas?