Donny Osmond Jokes Many Moms Were Probably ‘Screaming’ at Their TV Over 'Claim to Fame' Reveal (Exclusive)

Warning: This post contains spoilers for Claim to Fame season 2 finale.

Donny Osmond is super proud of his son Chris’ journey on Claim to Fame.

Ahead of the season 2 finale on Monday, where Chris placed third in the competition, the legendary singer, 65, spoke with PEOPLE about what it’s been like watching his son compete on the series — and ultimately outwit his costars about his celebrity relative. 

“Obviously I've done several [reality shows] with The Masked Singer and Dancing with the Stars but this is totally different. So I [told him], ‘Just be as clever as you can in this kind of situation.’ And boy, has he been clever,” he says of how his son played the game throughout season 2. 

“To be honest with you — of course, I'm going to say this because I'm biased — I think he's making the show interesting because they [couldn’t] figure out who he is,” he adds, noting there was definitely a generational gap at play. 

"This dynamic of having Chris on the show, that's what's making it exciting because the older generation, they know exactly what it is. And the younger kids, they have no idea,” he explains. “This happens to me all the time, especially in my Vegas show when I do ‘I'll Make a Man Out of You’ from Mulan. The younger generation come to my show but it surprises them that I'm Captain Shang and they can't get that. These millennials, they know the song, they know all about it, but they just don't know that it's Donny Osmond.”

“It's funny because I can only imagine how many moms are screaming at the television because he's done such a great job to keep it hidden,” he jokes. “Everybody has been screaming at the television set, ‘Oh, it's Donny Osmond.’”

Like the rest of viewers, Donny was completely in the dark about the show’s final outcome, noting that Chris wouldn’t reveal any spoilers to him. In fact, Donny says the entire Osmond family got together for a season 2 finale watch party at Chris’ in-laws’ house. 

“It's funny because Chris has been so tight-lipped about it,” he says. “I get it because when I was doing The Masked Singer, I couldn't tell anyone. I did finally tell my wife. It was quite funny because my oldest son, he figured it out. He said, ‘Dad, come on, come clean with me.’ I said, ‘Don, you can't say a word.’ So he didn't say anything to his children."

"And when I took my mask off, he was videoing my grandchildren watching the television, and they were screaming to the television, ‘Take it off. Take it off.’ And as soon as I took my mask off, they all screamed, ‘Grandpa!'" he recalls.

He adds that one of his favorite aspects of Claim to Fame is how it’s brought families together in the same way that his own variety show with his sister Marie Osmond did. 

“It is such an ingenious way to bring the family back together again,” he says. “Because when you think about the '70s, the Donny & Marie show was a family show that everybody just gathered around the television every Friday night. We don't have those kinds of shows, and this is a way to bring the family back together again, even though there's a generation gap, but that's what makes it unique.”

Following the season 2 finale, Donny hilariously reacted to the outcome on Instagram, sharing a photo of him sitting next to Chris during their watch party with his grandchild in his arms.

"For those of you who've been watching the ABC reality show, Claim to Fame, I thought my son, Chris, did an amazing job! He made that show so interesting because no one could guess which celebrity he was related to," he wrote, before playfully signing off the post, Elvis Presley, Billy Idol, John Mayer and more.

He ended the post writing, "PS. I don't like that lunchbox anymore! 😉" poking fun at the obvious clue the show used for Chris' relative which featured Donny and Marie on a lunchbox.

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Claim to Fame season 2 can be streamed in full on Hulu.