Oprah Winfrey Oprah Winfrey

Oprah Winfrey's big secret is that she has a little sister.

She held a family reunion on The Oprah Winfrey Show that aired Monday, and introduced her half-sister, Patricia.

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Patricia, who was given up for adoption by Winfrey's mother, Vernita Lee, in 1963, lived in foster homes until she was 7. By age 17, she was a single mother, and now has two grown children.

Winfrey commented that the Milwaukee woman has known about their relationship since 2007, but never tried to take advantage of the media mogul or sell her story. 

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Winfrey learned about Patricia just before Thanksgiving and was unaware at the time of the adoption since she was living in Nashville with her father. Lee said she later tried to find her daughter, but to no avail.

"I always had a feeling that she didn't need to give me up, and her saying that she came back to get me, it means a lot," Patricia said.

The 56-year-old talk show host said her mother still carries the shame of giving her daughter away but on Monday told her: "You can let the shame go. You can let that go."