Billie Eilish officiates at brother Finneas' wedding

Finneas O'Connell and Claudia Sulewski have married.

The music producer and his long-term girlfriend wed in Montecito, California, on Saturday, Vogue magazine reports.

Finneas's sister and musical partner Billie Eilish officiated the marriage, as shown in photos obtained by DeuxMoi.

Other celebrities in attendance included Nina Dobrev, Dax Shepard, Kristen Bell, Emma Chamberlain, Rachel Sennot, Stassie Karanikolaou, Jason Sudeikis, Carter Gregory, Justin and Hailey Bieber, and Eilish's boyfriend, Nat Wolff.

Finneas met Sulewski, an actor and skincare entrepreneur, on a dating app in 2018. In 2019, he told BuzzFeed that he wrote his song Claudia within hours of meeting her.

The couple has continued to collaborate creatively throughout their relationship. In 2022, Sulewski again served as the muse for Finneas' song Mona Lisa, Mona Lisa, starring in and directing the music video for the tune.

Finneas popped the question in a romantic sunset proposal in September 2025.

While appearing on The Tonight Show Starring Jimmy Fallon days after the proposal, Finneas opened up about what he learned from the moment and the stress he felt in keeping it a secret from Sulewski ahead of the big moment.

"I mean, I'm very relieved that it happened," he said. "I feel like it really taught me that I'm not cut out to rob banks or steal cars or something because I was keeping a joyous, happy secret for several weeks, and it ate me alive."