How to load an external SWF File on specified movieclip instead of stage?

programming flash
1

I want to load my external SWF file using the following code in “Panel4_mc” instead of on stage. How can I do it"

function btnClick(event:MouseEvent):void {

removeChild(loader);
var newSWFRequest:URLRequest = new URLRequest(“swfs/” + event.target.name + “.swf”);
loader.load(newSWFRequest);
addChild(loader);
}

Thanks.