[AS3] Show object under certain conditions?

[valadus]

I am making a game where once the player is close enough to an object, a "ray" appears, increasing the players score so long as they are close enough. I designed the ray animation and brought it over to my game's engine successfully, but now I am having trouble only showing it when the player is close enough.

This is the code I currently have:

blueXDist = Math.round(blueTarget.x - player.x);
            blueYDist = Math.round(blueTarget.y - player.y);
            blueDistance = Math.round(Math.sqrt((blueXDist * blueXDist) + (blueYDist * blueYDist)));
            var rayBeam:DisplayObject = new ray(blueDistance);

            if (blueDistance < 100)
            {

                blueHitTimes +=  1;
                trace("blue hits: " + blueHitTimes);
                closeToBlue(blueYDist, blueXDist, rayBeam);
            }
            else
            {
                removeChild(rayBeam);
            }
            if (player.hitTestObject(blueTarget))
            {
                trace("hit by a target");
            }

And here is the closeToBlue function:

public function closeToBlue(yDistance:Number, xDistance:Number, rayBeam)
        {
            var distance:Number = xDistance - yDistance;
            var radian:Number = Math.atan2(yDistance,xDistance);
            var rotationAmount = radian * 180 / Math.PI;



            addChild(rayBeam);
            rayBeam.x = player.x + 10;
            rayBeam.y = player.y + 10;
            rayBeam.rotation = radian * 180 / Math.PI;
        }

And this code returns this error in the output window at runtime:

ArgumentError: Error #2025: The supplied DisplayObject must be a child of the caller.
at flash.display:isplayObjectContainer/removeChild()
at classes::engine/loop()

Any suggestions are greatly appreciated. Thank you in advance for any and all help.

[holysocks]

check to see if rayBeam is there to be removed first

else
{
   if(contains(rayBeam)){
      removeChild(rayBeam);
   }
}