jQuery; Check if object has child $(this)

I wonder how I in the best way can see if a container div contains a child element. I have a click event that fires on a child of either div id=unread or div id=read. I want to check where this child is.

Something like this is what I'm thinking:

if ($("#unread").find($(this)))
    alert("unread");
else
    alert("read");

Edit: $(this) is a descendants two levels from #unread or #read.

Regards