Identical?

I was talking to a co-worker yesterday when I noticed a picture of his oldest daughter and remarked how much she looked like him. He then handed me a family picture of he, his wife and two daughthers, then said to me, "I think my youngest looks just like my identical twin brother."

I just stood there, completely confused, then asked, "Identical"?

Noticing my confused expression, he said, "Yeh. I know, it sounds weird, but she gives me the same facial expressions that he used to give me when we were kids."

Huh. That's something I never would have thought.