See Photos of Billie Eilish With Boyfriend Jesse Rutherford at her Celebrity-Packed 21st Birthday Party

Before the year was over, Billie Eilish made sure to shame 21st-birthday parties the world over with the celebrity-studded guest list at her Dec. 18 bash, featuring the likes of Hailey and Justin Bieber, Kendall Jenner, Lil Nas X, Doja Cat, Noah Cyrus, Avril Lavigne, Khalid, Barbie Ferreira, and Eilish’s boyfriend, The Neighbourhood singer Jesse Rutherford.

For the Christmas-themed bash, Eilish donned a Mrs. Claus outfit, blew the candles out on a candy cane-topped multi-tier birthday cake, and danced beneath a storybook sign that read, “A Billie Christmas To All And To All A Goodnight.” Her VIP guests stuffed themselves into a “Billie’s 21st”-themed photo booth, where Jenner, Hailey Bieber, and Jesse Jo Stark threw up middle fingers. Tributes to the birthday girl poured onto Instagram, where guests including Dove Cameron saluted their “fiery sagittarius cosmos sorceress, we all love you so much.”

Other guests posed for mirror selfies or gathered around the dance floor, where Eilish and Rutherford kissed in front of the crowd before raising their glasses in a toast. Hailey Bieber, never one to miss out on romance, shared her own snap kissing husband Justin in the photo booth.

Eilish, now 21, has been publicly dating Rutherford, 31, since Halloween, when she made their partnership Instagram official. “Yeah, I do [have a boyfriend now],” she told Vanity Fair in October, during her Same Interview, the Sixth Year video interview. “And it’s really cool, and I’m really excited, and I’m really happy about it.” Although their old man and baby costumes raised a few eyebrows earlier this year, Eilish has maintained that their age gap has little bearing on the respect between them: “You know, I don’t wanna be controlled,” she told Vanity Fair. “I wanna be trusted, and I wanna be able to have space, and I want love and attention, and equal admiration is really important. I just am really inspired by this person [Rutherford], and you know he’s inspired by me. It’s really cool.”

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