Need help with spacing out movieclips created with addChild

So I’m adding these movieclips which have textfields inside them and I’m trying to space each new movieclip. Currently they are being placed on top of each other.
_taskX and _taskY are variables which I define down there. Thanks for the help!

public function onClick(event:MouseEvent):void
            _taskX = 300;
            _taskY = 100;
            _newTask = inputTask_txt.text;
            _task = new Task();
            _task.x = _taskX;
            _task.y = _taskY;
            _taskY += _task.height + 20;
            _task.taskName_txt.text = _newTask;