"I called my mother to literally confront her and ask her, 'Is this true? Is this true?" Winfrey said. "She finally said, 'Well, yes, I think it's true.'
"There have been few times I've been anywhere and I haven't been sold out," Winfrey said. "There have been few times where you can bring anyone new into your life and not have that person in some way betray you or use you or take advantage of you."
Winfrey has never been one to shy away from sharing the details of her tumultuous family history, which has involved sexual abuse by family members and the death of a son shortly after she gave birth to him as a teenager.
"What's so extraordinary about Patricia and [her children] Andre and Aquarius is that they've known this secret since 2007 and she never once thought to go to the press," she said. "She never even thought to sell the story."
"When I heard this about you, I said regardless, I didn't know if it was true or not true that you are my sister, I had to meet you because I wanted to meet someone who had that type of character," Winfrey said. "So thank you."
Patricia and Winfrey met for the first time on Thanksgiving.
"You look just like Pat," Winfrey screamed, referring to the strong resemblance between her half-sister and her deceased sister Pat.
"We spent the rest of the afternoon getting to know each other," Winfrey said.
A few weeks after the meeting, Winfrey and Patricia visited their biological mother to ask her why she gave her baby up for adoption and why she hid it for so long from her family.
"I made the decision to give her up because I wasn't able to take care of her," Lee said in a pretaped segment of the show. "So when I left the hospital, I told the nurse I wasn't going to keep the baby.
"The nurse said, 'But she's such a cute little girl, why not?'" Lee said.
Lee said that she went back to the Milwaukee-area hospital after leaving to get the baby back but was told that the girl was gone.
"I didn't know if someone had adopted her or what," Lee said.
Asked why she kept her daughter a secret for so long, Lee said, "Well, because I thought it was a terrible thing for me to do. That I had done gave up my daughter when she was born."
Patricia, breaking into tears, said, "I am just trying to take it all in right now, because I never heard that I was a pretty baby.
"I always had a feeling that she didn't mean to give me up, and her saying that she came back to get me means a lot," Patricia said.