public class Index extends Sprite{
	internal static var _stage:Stage;
	public function Index() {
		_stage = stage;
		// var child:Child = new Child(this);
		var child:Child = new Child();
	}
}

public function Child() {
	// var grandchild:Grandchild = new Grandchild(target);
	var grandchild:Grandchild = new Grandchild();
}

public function Grandchild() {
	// trace( target.stage );
	trace(Index._stage);
}