Using a button in an addedChild mc not working

programming flash
1

[SIZE=2]Hi all, fairly new to AS3

[/SIZE][SIZE=2]I have a mc that adds a child from the library when a button in the navigation is clicked. In that child mc is a button to close it, but for some reason I can’t get it to work.

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references_btn.addEventListener(MouseEvent.CLICK, referencesUp);

this.isiClose_btn.addEventListener(MouseEvent.CLICK, isiHolderDown);


// ISI HOLDER ON/OFF FUNCTIONS

function references (e:MouseEvent){
    isiHolder_mc.addChild(new references_mc());
}

function referencesUp(e:MouseEvent):void{
var startValue:Number = isiHolder_mc.y;
var finishValue:Number = 28;
var duration:Number = .5;
var myTween:Tween = new Tween(isiHolder_mc, "y", Regular.easeOut, startValue, finishValue, duration, true);
myTween.looping = false;
references(e);
}

function isiHolderDown (e:MouseEvent):void{
var startValue:Number = isiHolder_mc.y;
var finishValue:Number = 768;
var duration:Number = .5;
var isiHolderDownTween:Tween = new Tween(isiHolder_mc, "y", Regular.easeOut, startValue, finishValue, duration, true);
isiHolderDownTween.looping = false;
}

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[/COLOR][/SIZE][SIZE=2]isiHolder_mc is the mc on stage, references_mc is the added child to isiHolder_mc, referencesClose_btn is the button to lower the isiHolder_mc back off stage.

Getting the mc to move up into position on stage and place the right mc from the library works fine. I just can’t get the close button on the mc to work.
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I get this error:

TypeError: Error #1010: A term is undefined and has no properties.

Any thoughts?
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