Billie Eilish Kisses Boyfriend Jesse Rutherford at 21st Birthday Party

Billie Eilish sealed her birthday with a kiss.

The “Therefore I Am” singer rang in her 21st trip around the sun with a party that had no shortage of celebrity guests—including her boyfriend Jesse Rutherford, who shared a sweet PDA moment with Billie during the celebration.

As seen in a video reposted to Billie’s Instagram Story on Dec. 18, the Grammy winner and Jesse kissed amongst a crowd of party guests at the event. Those on that very guest list included Dove Cameron, Lil Nas X, Barbie Ferreira and Avril Lavigne.

As for what party attendees got up to at the celebration, Billie reposted images and videos of the bash’s Christmas-themed decorations, guests in festive costumes, a peppermint adorned cake and black-and-white pictures taken at a photo booth.

Billie and Jesse sparked romance rumors in October, when they were spotted out for a meal together in Los Angeles. That same month, the duo were also seen hitting up Universal Studios’ Halloween Horror Nights and out on a dinner date that featured plenty of PDA.