Stacking order for movie clips

Hi Have have 3 buttons made that when clicked on it loads a movie clip. I have all that done but I want to know if you can change the stacking order so that if you click on button three that will load, and then if you click on button two I want that movie clip to go over the first movie.

And lets say if you want to go back to that first movie, I want the second one to go in the background and the other one to be view able.

this is a preview of what I have done.click

Im not sure if I make any sence :S