Seperated at Birth?

I'm in the midst of reading Alison Weir's new biography of Mary Boleyn (which I will review once I've finished it).  While flipping through the photos in the middle of the book, I noticed a curious thing; how much Anne of Cleves and Katherine Howard resemble each other, at least in their portraits.

This is a portrait of Anne of Cleves, probably the same one that Henry VIII saw, that charmed him. Of course, we know from history that Henry felt that he had been duped when he finally met his new bride in the flesh, and discovered that she didn't exactly look like this portrait!

This is a potrait that is assumed to be of Katherine Howard, Henry VIII's fifth wife and Anne Boleyn's cousin. If you look closely at the eyes, nose and mouth, they are remarkably similar in both paintings! Both portraits were painted by Hans Holbein the Younger, which probably explains why there is such a similarity in their looks.  Apparently Holbein wasn't as good at faces as he was at painting everything else!