The 83-year-old Motown legend makes a shocking claim in a new interview.
The 83-year-old music icon opens up about his and Ross' longtime friendship, even claiming that they had a year-long affair during his first marriage to Claudette Rogers.
When asked in an interview with The Guardian whether he and Ross ever had "a thing," he replies, "Yes, we did," adding that it lasted "about a year."
"I was married at the time. We were working together and it just happened," he shares. "But it was beautiful. She’s a beautiful lady, and I love her right till today. She's one of my closest people. She was young and trying to get her career together. I was trying to help her. I brought her to Motown, in fact. I wasn’t going after her and she wasn’t going after me. It just happened."
Robinson says that it was Ross who decided to end things.
"After we'd been seeing each other for a while, Diana said to me she couldn’t do that because she knew Claudette, and she knew I still loved my wife. And I did. I loved my wife very much," he says.
The Guardian reporter goes on the question whether Robinson is familiar with a rumor that he and Ross are the biological parents of Michael Jackson.
"They say I’m the baby daddy?" Robinson exclaims, his voice rising and giving way to a laugh. "They say Diana Ross and I had Michael? ... Oh my God! I never heard that one, man! That's pretty good. That’s funny! That’s funny!"
Robinson then declares he must call Ross to ask if she's heard the same story.
The Motown legends have been friends since Robinson was 10 years old, when Ross moved onto his street with her family. Also living in their neighborhood were Aretha Franklin and her brother, Cecil.
"It's beautiful to know we were kids playing together. And these people are some of the most famous people in the world now," he muses. "We had such joy."
Robinson is also asked in the same interview whether he ever had a romantic relationship with Franklin, to which he responds, "No, just friends."
"I do admit when I was about 15 I had a crush on her," he adds. "Hehehe! Yeah, she was fine!"
The "Tracks of My Tears" singer was married to Rogers from 1959 to 1986. He wed his second wife, Frances Glandney, in 2002.
"I learned that we are capable of loving more than one person at the same time," he says of his relationships. "And it has been made taboo by us. By people. It’s not because one person isn’t worthy or they don’t live up to what you expect -- it has to do with feelings. If we could control love, nobody would love anybody. Nobody would take that chance. Why would you put your heart out there for somebody to be able to hurt you like that and make you able to have those feelings?"
Today, the living legend is gearing up to release his first studio album in nearly a decade, GASMS, out April 28.
Earlier this year, Robinson told ET that he still has one big Hollywood item left on his bucket list.
"If there's anything left on my bucket list, it would be that I would like to make a movie, a good movie," he told ET. "... I'd like to be in a really good movie and be a character."
While Robinson hopes to play a character in a flick, lots of people want a Broadway show or a movie to be made about his life, both of which "some people have approached me to do it."
Any potential project about his life, Robinson said, is "gonna be very candid."
"I might as well be candid. I don't want to sugarcoat it... There's going to be my ups and my downs, and my positives and my negatives, and all that has to be included, if it's going to be real," he said. "I want it to be real, so people can get a good feeling of what my life has been and what it's like."
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