Joe Jonas is getting closer to being a married man.
“It’s our bachelor party as much as it’s for him. It’s really for all of us,” said Nick, 25. “We got no plans yet, [but] it’s gonna be very respectful. We’re gonna have some fun. We have to! He’s gonna get married. It’s a big deal.”
The entertainer also turned heads on the carpet with his form-fitting dress shirt that accentuated his bulging biceps.
After Joe, 28, and fiancée Sophie Turner, 22, announced their engagement last year, Nick gushed about his future sister-in-law.
Check out PEOPLE’s full Billboard Music Awards coverage to get the latest news on music’s big night.
“I can tell you that he found his partner and love of his life,” the “Jealous” singer told Entertainment Tonight. “That’s all that matters. It’s a beautiful thing.”
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The engaged couple began dating in late 2016 and had a whirlwind romance before Joe popped the question last October.
“Everybody’s very, very happy for them and their family and friends are all thrilled. Everyone loves them together,” a source previously told PEOPLE of the exciting news. “She’s young but is beyond her years and is crazy, crazy mature. He’s never been like this with a girl.”