How to bind one draggable DIV to another?

How to bind one draggable DIV to another?

Hi guys, Say I have Div1 and Div2. I want to make that when a user is dragging around Div1, Div2 should also drag along. Any ideas how do I make it?

Here's what I got so far...
  1. $(document).ready(function() {
        $
    ("#apDiv1").draggable();
        $
    ("#apDiv2").draggable(); //<- how do I link it do Div1 ?
    });


Thanks