After nearly five decades of marriage, Donny Osmond is opening up about the unforgettable moment he knew he was going to marry his wife, Debbie—and it just so happened to involve an Elton John concert and a little sibling rivalry.

“She dated my brother, and I stole her from my brother,” Donny told Fox News Digital with a laugh. “That’s a true story.”

At the time, Donny was dating a girl named Tammy while his brother Jay had taken Debbie out. The four went on a double date to see Elton John perform live, and that’s when fate stepped in.

“When Elton sat down at the piano to sing ‘Your Song,’ I looked over at my brother’s date and thought to myself, ‘I think I’m going to marry that girl someday.’ And I did.”

Donny even shared the romantic story with Elton John years later, jokingly blaming him for the love story that blossomed that night. “I said, ‘You’re responsible for my marriage.’ He thought that was kind of funny.”

Their story goes back even further. The two first crossed paths as children—Donny was 5 and Debbie was just 3—at a Montana airport during a layover while Donny and his brothers were touring with Andy Williams. Debbie’s family spotted the famous Osmond kids and asked for autographs.

“She was 3, and I’ve literally known her all my life,” he recalled.

Donny and Debbie eventually married in 1978 and went on to raise five sons: Don, Jeremy, Brandon, Chris, and Josh. Nearly 47 years later, their bond remains strong.

“It’s a lifetime of bliss,” Donny shared. “She’s an amazing woman and very patient.” That patience, he added, came in handy during his time on Dancing with the Stars, where Debbie had to watch him twirl other women across the dance floor.

Their lasting love is built on friendship, trust, and shared history. “We were friends before we were married,” Donny said. And that foundation has stood the test of time in both love and show business.

From a childhood autograph to a life together built on faith, family, and show-stopping performances, Donny and Debbie’s story proves that sometimes, love really does start with “Your Song.”