photo nick-carter-300_zpsec51e2d8.jpg

Backstreet Boy Nick Carter is getting married Saturday – and it's something the groom himself thought would never happen.

"I said I'd never get married," the 34-year-old told PEOPLE last year, but he's making it official with a Southern California wedding to his fiancée, fitness expert and actress Lauren Kitt.

The happy couple, who got engaged in February 2013, held a rehearsal dinner on Friday night.

Carter's bandmate A.J. McLean posted on Instagram Friday that he was getting ready to head to the rehearsal dinner for "the wedding that most of u thought would never happen, but I'm so happy it is finally!"

Backstreet Boy Howie Dorough also attended the pre-wedding bash, which was Arabian-themed.

 photo instacarterrehersaldinner_zps6e9c74f9.gif

In fact, in an interview with PEOPLE last year, Carter said that it was Dorough who helped him get up the nerve to propose to Kitt. "I asked Howie [for advice]. I was like, 'I love her, and I don't want to lose her.' And he was like, 'Just do it!' "

Carter popped the question with an enormous, 7-carat pear-shaped diamond in the Florida Keys, after sailing Kitt to a nearby island. Things didn't totally go according to plan. "The boat was barely running. It died, like, four times," he said.

They finally made it to the island and climbed a hill, where Carter surprised Kitt. "I got down on my knees and did that whole hoopla," he said. "She was like, 'Are you serious?' And started crying. Now we call it Engagement Island."

On April 5, Kitt posted a photo on Instagram of her and her father, saying, "Next Saturday the first man I ever loved with give me away to the love of my life. I love you Dad."