Linking frames?

[Rythal]

I've got 3 CreateFrames:

MainWindow of size 300x300 and set for resize
ChildFrame of size 270x295 centered in the middle of MainWindow
ChildFrame2 of size 30x295 at the very top of MainWindow

ChildFrame2 is set to allow moving, I was trying to make it so the entire MainWindow moves with it, but they don't seem to be linked even tho they are parent/child (as in when I move it only ChildFrame2 moves)

How do I link them together so everything moves?