ActionScript 3.0 :: Removing Child Movie Clip With Alpha Transition?

I've been trying to find this topic on the internet for what seems like forever but haven't had any luck. What I'm trying to do is remove a child movie clip and have an alpha transition when it is removed.

What I have so far can be found at: [URL]

Basically what I'm trying to do is when the video player is closed, instead of simply disappearing, I want it to fade to an alpha value of zero

this is the code I have so far:

ActionScript Code:
stop ();
MC_btn.addEventListener(MouseEvent.CLICK, vimeo_embed);
function vimeo_embed (e:MouseEvent):void {
var OpenEmbedPlayer:Vimeo_MC_PU = new Vimeo_MC_PU();

[Code].....