removeChild() before addChild()?

Hi all. I have a flash movie where I’m trying to load movies to the stage from it’s library. I’ve been able to successfully do this, but how can I test if the movie is already on the stage? Right now, I click a button that loads a movie from the library to the stage, but when I click it again, you can see it adding another instance of the movie clip every time I click the button. I’d like it to only add the clip if it’s not already there. Here is my current code:

needTab_mc.addEventListener(MouseEvent.CLICK, swapTab);

function swapTab(event:MouseEvent):void {
    var currActive =;

    if (currActive == needTab_mc) {

        var need:mcNeed = new mcNeed();
        need.x = 41.5;
        need.y = 74.5;


Right now, it just keeps adding the movie over and over again or every time I click the needTab_mc. Thanks!