Happy National Twin Day (Dec. 18)! Enjoy this story from earlier this year about identical twins who ended up marrying identical twins ... even though it was the furthest thing from their minds.

Identical twins do not share identical fingerprints. Fingerprint patterns are developed early during pregnancy, and the environment of the womb has a lot to do with how the prints are shaped.

Identical twins share the same genes. But this does not mean the twins will be identical in every way. One twin may have a particular medical condition, while the other does not.

Shocking images of identical twins who live very different lives ... They found women who had been divorced looked older than their married or single counterparts. The twin who was divorced ...

MZ twins are generally assumed to be genetically identical, although some genetic and epigenetic differences have now been described. A newly published finding that phenotypically concordant as ...

"Although identical twins may look the same to you and me ... As young men, they'd both married women named Linda, and then divorced them. Their second wives were both named Betty.

Married at First Sight alums Jamie Otis and Doug Hehner have shared the specific ways they’re able to tell their newborn identical twins apart. Jamie, 38, and Doug, 41, welcomed twin sons ...