Why, it's quite obvious---one is the gay twin of the straight brother. It is left as an excercise for the student to determine which is which...
I knew there was a fake here... judge for yourself. Can you spot the difference?
http://www.lpsg.org/gallery/showphoto.php/photo/35546/cat/500/ppuser/93466
Problem is, who's the real one? Or did they both steal?