Tweenlite keeping reference?

Having a little issue with TweenLite seemingly keeping a reference to my clip. In one method I do:

detail.btnBack.addEventListener(MouseEvent.CLICK, removeDetail, false, 0, true);

Then I have the removeDetail, and killDetail methods:

private function removeDetail(e:MouseEvent):void
{
TweenLite.to(detail, .5, { alpha:0, onComplete:killDetail } );
}

private function killDetail():void
{
removeChild(detail);
}

This seems to work, except the removeChild is not working - the detail clip is faded, and killDetail is called, but the clip remains. If I remove the TweenLite fade and do the removeChild right in removeDetail() the clip is fully removed from the display list. I’ve tried doing a TweenLite.killTweensOf(detail) within the killDetail(), before removing child on it, but that doesn’t help.

I can’t recall ever having an issue like this with TweenLite before.