EXCLUSIVE: Backstreet Boy Brian Littrell's Son Baylee Follows in His Performing Footsteps

The Backstreet Boy and his son open up to ET about Baylee making his Broadway debut in 'Disaster.'

He can sing, he can dance, and he’s the son of a Backstreet Boy!

At 13 years old, Baylee Littrell is following in his father Brian Littrell’s footsteps with his own budding singing and acting career. Earlier this week, the youngest Littrell officially made his Broadway debut in Disaster!, a new jukebox musical and parody of those outrageous ‘70s disaster films.

“I never knew that Broadway was going to come into the mix,” Baylee tells ET, revealing that he started “jumping up and down, screaming” before running around his room upon hearing the news that he landed the part. But his father knew better.

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“Baylee’s worked hard. He's been all over the globe with the Backstreet Boys and he's seasoned,” Brian says. “He loves characters: he loves Carol Burnett, he loves Tim Conway. He’s an old soul.”

While Disaster! is his first Broadway show, Baylee has been performing since he was seven years old, when he sang at his parents’ vow renewal ceremony. By the time he was nine, he was opening for his father’s band during their 2012 tour, NKOTBSB, with the New Kids on the Block. (Though, his first, adorable brush with the stage was as a toddler, when he introduced the band during their 2008 Unbreakable world tour.)

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But much of Baylee’s old soul likely comes from his childhood battle with Kawasaki syndrome, an autoimmune disease that most often affects young children. Having survived, Baylee knew he could face whatever challenges -- on stage or off -- that lied ahead.

“It gave me a lot more strength and courage,” he says. “I remember I walked out of the hospital in a Batman costume. I was like, ‘I walked out of here and I survived this and everything is going to be amazing.’”

On stage, Baylee pulls double duty playing twin siblings, Ben and Lisa, switching in and out of a pigtailed wig throughout the show. It’s one of the more technically challenging roles, with the actor even singing a duet with himself.

“It was really hard at first,” he admits, eventually feeling comfortable with the part after an Off-Broadway run. “It's just so fun and so fast-paced, going back and forth. It’s the best number of the show, I love it.”

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“When the crowd is laughing, it makes me feel really good,” the young performer adds. “It's cool.”

With his father back in the studio with the Backstreet Boys and the band contemplating a Las Vegas residency, it’s any wonder if Baylee aspires for a long-running career such as his.

“I'd like to follow in his footsteps -- solo,” Baylee teases.

Disaster! is now playing at the Nederlander Theatre in New York City.