How to reference a child

Got this code

function onOver (event:MouseEvent):void
	var panel:MovieClip = new storePanel();
	panel.x = + -25;
	panel.y = + -128;
	panel.alpha=0;, .7, {alpha:1, ease:Sine.easeOut});
	panel.storeText_txt.text = walesArray[buttonArray.indexOf(];

function onOut (event:MouseEvent):void

Firstly removeChildAt(this.numChildren-1); is working but is this the best way of removing the child?

More importantly, in the onOut function I want to tween out the panel object but I don’t seem to be able to reference panel. For instance even if I said panel.alpha = 0; I get an error, why is this? and how can I talk to my newly created panel movie clip in the onOut function.

Thanks guys, I know I’ve asked loads recently but I’m really getting into my AS. I know I don’t know much but I’m really wanting to learn more!