Making graphic control show up on top of others

[greenmachine]

So I have this GUI, and I have a picture in the middle of the GUI. Now, what I am trying to do is use the graphic control to draw on top of the picture (in certain circumstances). I don't want the graphic to be on top of the picture for about 90% of the script, but then on certain occasions I want to be able to draw a line on top of the picture without covering the rest of the picture with the blank graphic control (which would cover the picture). I'm not sure how this would work.

I tried making a graphic control first to put it underneath the picture, and then drawing to the graphic control, but that keeps the lines underneath. Then I tried making the graphic control after the picture control, thinking that would put the whole thing on top of the picture. It didn't. Then I tried deleting the graphic control and remaking it whenever I wanted to draw - still nothing. It seems that no matter what, the graphic control is always behind the picture control. Does that mean I won't be able to draw on top of my picture? Or are there ways around this?

I'll post code or a screenshot if it's necessary, just say so.