Loading/Unloading Movieclips

var p01:MovieClip = new project01();
 
	p01.x = 0;
	p01.y = 0;
	addChild(p01);
	
var p02:MovieClip = new project02();
 
	p02.x = 50;
	p02.y = 0;
	addChild(p02);
	
var p03:MovieClip = new project03();
 
	p03.x = 100;
	p03.y = 0;
	addChild(p03);
	
p02.addEventListener(MouseEvent.MOUSE_OVER, p02Over);
p02.addEventListener(MouseEvent.MOUSE_OUT, p02Out);
 
function p02Over(Event:MouseEvent):void {
	
	p02.alpha = 0.5;
	}
 
function p02Out(Event:MouseEvent):void {
	
	p02.alpha = 1;
	}
	
p02.addEventListener(MouseEvent.CLICK, p02Click, false, 0, true);
 
function p02Click(Event:MouseEvent):void {
	
	if(parent.contains(gallery01)) {
		removeChild(gallery01);
	}
	
	var gallery02:Loader = new Loader();
 
	gallery02.load(new URLRequest("galleryHolder02.swf"))
	
	gallery02.x= 155;
	gallery02.y = 0;
	this.addChildAt(gallery02, 2);
 
}