The blond haired boy band staple popped the question -- and got a resounding yes.

Carter proposed to his girlfriend of four years, actress and fitness expert Lauren Kitt, this week -- and he'd been holding on to her engagement ring for two weeks leading up to the big reveal! "I was like, 'I don't want it anymore!' It was driving me insane," Carter told PEOPLE. "I just wanted to get it out of my hands and on to hers."

He announced the engagement on Instagram, posting the above photo with the caption, "Big question. Great answer." Aw!

The 'I Want It That Way' singer took Kitt on a romantic boat ride to ask for her hand, but it didn't go that smoothly at first. "My boat was in such bad condition because I hadn't used it for, like, six years. It took me five days literally on my hands and knees, scraping up my body [to fix it,]" Carter said. "The engine wasn't complete yet but we still decided to go out."

After a few engine stalls, the couple and some close friends and family made it out to an island Carter spent a lot of time on as a kid on Wednesday (Feb. 20). Carter got down on one knee and offered up a seven-carat diamond ring to his lady love.

"She said, 'Yes,' and I'm, like, 'I don't know what to do," Carter gushed. "She said, 'You're supposed to put it on my finger.' So I did. I was in shock." Cute!

Kitt was taken by surprise. "I wasn't expecting it," she said. "It just felt very surreal. We both are just so happy in love right now and on cloud nine."

As for wedding planning, it may not happen right away. "Our first thought was, 'We need to contact the Backstreet Boys and find out when their schedule will permit,'" Kitt said. "It's not up to us. It's up to the schedule. We're just excited and looking forward to the next chapter of our lives."

Watch the Backstreet Boys 'As Long as You Love Me' Video

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