Remove Dynamically-Added .swf

Hi folks. I have an AS3 app that allows users to pick from a menu of AS2 .swf movies to load into a MovieClip. Users are allowed click to view one movie, but if they change their mind and click a different clip, it should unload/delete/remove the .swf that’s currently playing so that the user don’t have overlapping movies playing at once. If someone can help me to accomplish this, I would appreciate it! Here’s what I’ve come up with, but it doesn’t work:

try {
//(see the load code below) If a .swf is already loaded, remove it
var clipToDelete:Loader = Loader(parentClip.getChildAt(0));
parentClip.removeChild(clipToDelete);
clipToDelete = null;
}
catch (e) {
}

//Load a .swf into parentClip
var loader:Loader = new Loader();
parentClip.addChild(loader);
loader.addEventListener(Event.ADDED, parentClipOnLoad);
loader.load(new URLRequest(“someMovie.swf”);

Thanks!

Andy