Janet Mock's Surname Comes From Her Third Great Grandfather's White Slave Owner

On the fourth season of PBS' series, Finding Your Roots, Dr. Henry Louis Gates Jr. sits down with transgender journalist Janet Mock to learn about her ancestors' history and how their surname was originally chosen. This discovery underlines America's dark, oppressive past, but ultimately helps Janet come to peace with her family background.

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Louis Gates Jr. traces the surname back to Louisiana, presenting Janet with the official registration of her third great grandfather, who was owned in 1860 by a white man named William T. Mock. The document, called a "Slave Schedule," shows William also had five other nameless slaves. Janet's ancestor was a "piece of property with no name," Louis Gates Jr. says, so he adopted "Mock" as his own.

An upsetting finding that's certainly not limited to Janet's ancestry, she calmly absorbs the information with a smile. "Well it's interesting to see where Mock came from, and then my attachment to that last name that it goes all the way through me and my brother, who now has a child," she says. "We know that it goes back to a white man named William."

When Louis Gates Jr. asks what it's like for Janet to see her family's Slave Schedule, she describes it as a "reconciliation," having chosen her first name. "I chose Janet, and to see that then, my great great great grandfather chose Mock... he could've changed it to something else if he wanted to," she says. "But he chose that name and so for me there's a reconciliation between those parts of myself: the identity that is mine and the identity that is my family's."

Janet's episode of Finding Your Roots also follows her maternal roots to Hawaii, where her second great grandparents were farm laborers that resisted U.S. encroachment on their native culture by refusing to learn English.

Watch an exclusive preview, below, and the full episode Tuesday, October 24 on PBS at 8 pm EST.