How to make a button to overlay all objects?

Question

I'm currently making a flash application. In the application, I'm loading an swf file inside a frame. Here's the code:

stop();

var url1:URLRequest = new URLRequest("Complete The Words Game 1.swf");
myLoader.load(url1);
addChild(myLoader);
myLoader.scaleX = 1.8;
myLoader.scaleY = 1.8;
myLoader.x = 190;

addChild(backtopractice_button);
backtopractice_button.x=20;
backtopractice_button.y=610;
backtopractice_button.addEventListener (MouseEvent.CLICK, backtopractice);

And I want to bring the "backtopractice_button" to the very front to overlay everything, even the SWF file too. Is it possible to do this? and how do I do it? Thanks.