ActionScript 2.0 :: Referencing Instance Name With Variable In Prototype Call

I'm trying to reference an instance through the use of a variable in my call to a prototype. The variable is myVar and contains the instance name to which I want to apply the resizeTo prototype. My syntax is incorrect.

Code:
on(release){
//disregard this line
this.swapDepths(this._parent.getNextHighestDepth());
//this is calling a prototype named resizeTo
this.resizeTo(150, -100, -100);
//Setting instance name of another movie
myVar = "green";
//Trying to drop that instance name into my next prototype call
this._parent.myVar.resizeTo(100, _parent.old_X, _parent.old_Y);
}