What Is a Mirror Twin?

Kelly McGonigal says she and her sister are mirror twins. Kelly is left-handed and her sister is right-handed, and their moles sit as if the two of them had been pressed together in the womb. She sometimes wonders whether their brains developed differently because of that. She got interested in meditation because she was always trying to make the present moment better, including when she was suffering and needed a way to be okay right then.

They grew up with parents who were educators, strict about some things and loose about others. The sisters were often home alone and were not allowed to cross the street. They could watch any movie and read any book. They were the only two students in their high school who were kept off the senior trip, because their parents feared they would be corrupted and thought Kelly would get into trouble if she were allowed out of the house. She thinks she would have been more adventurous and would have had more fun. Keeping someone contained for 18 years, she says, is a reliable way to make that person adventurous.