Though she didn't disclose with whom, the talk show titan shared that it involved something she's learned about recently and is only known to her closest friends.
"I thought I'd seen it all. But this, my friends, is the miracle of all miracles," Winfrey said in show commercials.
Having performed numerous family reunions on her talk show over the years, Winfrey stressed the impact of her own family reunion by having the word "miracle" appear on screen.
"I was given some news that literally shook me to my core. This time, I'm the one being reunited," she shared. "I was keeping a family secret for months, and on Monday you're going to hear it straight from me."
BlackVoices.com has learned that Winfrey's big announcement is that sometime around Thanksgiving of last year, she discovered she had a half-sister she never knew about.
The 56-year-old television mogul had believed for years that she was her parent's last living child – younger siblings Jeffrey and Patricia are both deceased.
Winfrey learned that her mother, Vernita Lee, had another daughter who, oddly enough, is also named Patricia. Sources tell BlackVoices.com that the two have already met in person, a DNA test has been conducted and Winfrey's talk show reveal is only to introduce her sister to the world so that the media does not exploit the story.
At press time, details were sketchy as to why Winfrey was unaware of her sister's existence until now. BlackVoices.com has learned that Patricia was raised in the foster care system after Lee gave her up for adoption.
Born in Kosciusko, Miss., to her unmarried teenage parents, Vernon Winfrey and Vernita Lee, Winfrey was raised at various points in her life by a grandmother, Hattie Mae Lee; her parents; and even a stepmother according to biographies on her.
In a December interview for an ABC special with Barbara Walters, Winfrey acknowledged that she provides for both of her parents monetarily.
When asked about her relationship with her parents, she confessed she isn't extremely close to them.
"I would not say that I have been the kind of daughter that calls home every week and is checking in with my parents," she told Walters. "I wouldn't say that we're terribly close."
Winfrey, who launched her own television network called OWN on Jan. 1, went on to say that things with her and her father were "fine," though she struggled to find words to describe her relationship with her mother.
Ultimately, Winfrey would declare during that interview that her best friend Gayle King was "the mother I never had."
Winfrey will formally make the announcement about Patricia on her talk show at 9 a.m. CST, which is when her show airs live in Chicago. Check local listings in other markets.
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