Oprah Winfrey’s big family secret? The talk-show queen announced on ‘The Oprah Winfrey Show’ Monday that she has discovered a half-sister named Patricia, who was given up for adoption as a child. She said her mom secretly gave Patricia up in 1963. She is 48, has two adult daughters and lives in Milwaukee.

It’s been a revelatory year for Winfrey, who, as her legendary daytime show winds down its 25th and final year, has stepped out of her comfort zone to address a number of rumors about herself, including talk that her friendship with Gayle King is actually a romantic relationship and her thoughts of suicide as a teenager after she learned of an unwanted pregnancy.

“I was given some news that literally shook me to my core. This time, I’m the one being reunited,” Winfrey said in advertisements for today’s episode of ‘Oprah.’ “I was keeping a family secret for months, and on Monday you’re going to hear it straight from me.”

Earlier Monday, Black Voices reported that Winfrey learned sometime around Thanksgiving of last year that her mother, Vernita Lee, had another daughter. Winfrey, 56, believed for years that she was her parents’ only surviving child after her two younger siblings, Jeffrey and Patricia, passed away. Patricia was reportedly raised by another family, and either her adoptive parents coincidentally named her Patricia, which was also the name of Winfrey’s known deceased sister, or Lee

“adored the name Patricia so much she named two children that.”

Sources told Black Voices that Winfrey and Patricia have met in person and today’s reunion special is Winfrey’s opportunity to introduce her sister to the public.

As soon as Winfrey announced that she would reveal “news that literally shook me to my core” about “a family secret,” the Internet lit up with speculation.

“There has been speculation in the past that Vernon Winfrey is not her actual biological father,” In Touch Weekly senior editor Amy Palmer told CBS News, “so this is something people are saying it could be.”

Others — including Kitty Kelley, who famously wrote an unauthorized biography of Winfrey last year — had been correctly claiming that Winfrey would reveal a long-lost family member.

Why Winfrey did not know of her half-sister’s existence until late last year remains unclear.

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