On the show (airing today; check your local listings), Osmond, 51, denies speculation that her son was gay and took his life this past February because his sexuality conflicted with his Mormon upbringing.
"My son was not gay," she said. "He wanted to be married and have a family and travel all over the world. And it wouldn't matter if he was — I have a daughter who's gay.
"She was the most offended by [the rumors]," she said, adding that her daughter felt they implied that "everyone who's gay commits suicide."
Osmond also denied that her son — who entered a rehab at age 17 — was under the influence when he took his life.
"My son was clean when he jumped," she said of the teen, who was a student at L.A.'s Fashion Institute of Design and Merchandising. "There were no drugs in his system, but I believe the ramifications were there."
He was just lost, she said.
During her 2007 stint on Dancing With the Stars, he tried to commit suicide.
"He promised he would never do anything like that again and I believed him," she said. "Whatever his reality was, I do believe that there are moments when you slip into insanity and you no longer think rationally. I believe that's what happened."
On the show, Osmond also performed an opera song she dedicated to her late son.
"I know I'll see him again because of what I believe," she said before her performance.
She couldn't make it through the entire song without tearing up.
"It's very hard, very hard," she said afterwards. "But it's a gift of love for him."
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