Estoy creando un juego de estilo pacman. Estoy tratando de eliminar una instancia de MovieClip usando removeChild (). Cuando el "cuadro" de la instancia de MovieClip llegue al "círculo" de la instancia de MovieClip, el círculo se eliminará del escenario.

Recibo el siguiente error a continuación:

ArgumentError: Error # 2025: El DisplayObject suministrado debe ser un elemento secundario de la persona que llama. en flash.display :: DisplayObjectContainer / removeChild () en Move / eatCircle ()

package {
       import flash.display.Sprite;
       import flash.display.MovieClip;
       import flash.events.Event;
       import flash.events.KeyboardEvent;
       import flash.ui.Keyboard;

       public class Move extends MovieClip {

       var ScoreObjects:Array = new Array(); // creates ScoreObjects array


          private var inertia:int=8; //amount of friction

       var score_field:String;
       //var point:MovieClip;


     // Constructor--------------------------------------------------------------------
          public function Move() {
             init();
          }

     // function init -----------------------------------------------------------------
       function init():void {

             //stage.frameRate=60;
        var score_field:String="";

      ScoreObjects[0] = new Circle();
      ScoreObjects[0].amount = 1; // amount of point
      ScoreObjects[0].name = "circle";


             stage.addEventListener(Event.ENTER_FRAME, frameloop);
             stage.addEventListener(KeyboardEvent.KEY_DOWN,keyDownEvent);
             stage.addEventListener(KeyboardEvent.KEY_UP, keyUpEvent);

        box.addEventListener(Event.ENTER_FRAME, eatCircle);
        wall.addEventListener(Event.ENTER_FRAME, hitWall);

        stage.addChild(ScoreObjects[0]); // add Score Objects to stage ------------------------------
        trace(ScoreObjects[0]);

        ScoreObjects[0].x = 105;
        ScoreObjects[0].y = 233;

          }

     // function eatCircle --------------------------------------------------------------
     function eatCircle(event:Event):void {

      if (box.hitTestObject(ScoreObjects[0])) {
        trace ("I ate the circle");
        removeChild(ScoreObjects[0]);
        //calcScore();
       } else {
        trace ("I didn't eat the circle");
       }
     }



       }// end of class
    }// end of package