07/25/2013 10:01 am ET

Oprah's Sister, Patricia Lee, To Appear On 'Where Are They Now?' (VIDEO)

In 2010, Oprah discovered a bombshell family secret: She had a half-sister who had been put up for adoption at birth. A few months after learning the secret, Oprah and her family chose to reveal the news on their terms, and Oprah introduced the world to her half-sister, Patricia Lee, on an episode of "The Oprah Winfrey Show." The introduction, as can be seen in the video above, was an emotional one.

Now, "Oprah: Where Are They Now?" is catching up with Patricia in a new episode airing this Sunday at 10 p.m. ET on OWN. But where did this incredible story begin? Milwaukee, Wisconsin.

Nine years after Oprah was born -- after she had already begun living with her father in Nashville -- Oprah's mother gave birth in Milwaukee to a baby girl she immediately put up for adoption in 1963. Patricia bounced around from one foster home to another before being adopted and spent decades wondering about her birth mother and biological family. Then, in 2007, Patricia requested her birth records and learned that she had three biological siblings. She didn't know their names, but did learn key information, including the fact that two had since passed away. One, however, was still living.

As fate would have it, Patricia turned on the television one day to see a local news story interviewing Oprah's mother, Vernita Lee. During that interview, Patricia noticed that many of the details Vernita shared lined up exactly with what she had read in her birth records. Could it be? Patricia wondered.

Putting the pieces together, Patricia finally tracked down Oprah's niece, Alisha, who owned a Milwaukee-area restaurant. Alisha is the daughter of one of the siblings who had passed away and was stunned at how much Patricia looked like her own mother. The women took DNA tests and the truth was confirmed: Patricia had found her biological family.

On "The Oprah Show" in 2010, Oprah shared that she was just as shocked by the news. "I can't tell you how many times I've done a story like this on 'The Oprah Winfrey Show' and seen the surprise on somebody else's face," Oprah said. "It's not something I ever thought would happen to me or our family."

But there's something even more remarkable about this story, Oprah says. In the video above, she fights back tears as she shares something special about Patricia that touched her in an extraordinary way.

So what is their relationship like today and what has Patricia been up to since discovering she is Oprah's half-sister? Tune in to "Oprah: Where Are They Now?" to find out, airing Sunday, July 28, at 10 p.m. ET on OWN.



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