I've a mdiform where sometimes a mdichild (one or more) are loaded and sometimes there isn't any mdichild form loaded.

I want to use keyboard shortcuts for specific tasks (for example control+B to show a mdichild, alt+2 to change graphic parameters of an opened mdichild, etc). I've been looking in the forum and some guy said to use a picturebox control in the background of the mdiform and at the end of the keydown event use
Code:
Picture1.SetFocus
The problem is when I use that solution, no mdichild form can be seen on the mdiform. I think the mdichild is behind of the picturebox control.

So, what solution can I use? Remember that the mdiform has some key shortcuts and the mdichild forms have different key shortcuts.