Montecito, California - Billie Eilish's brother, Finneas O'Connell, married Claudia Sulewski over the weekend – and the pop star played a huge role in their nuptials!
Per Vogue, Finneas and Claudia tied the knot in a lavish, star-studded ceremony in Montecito on Saturday.
The 24-year-old singer and sister of the groom officiated the wedding and was captured looking the part in a stunning, off-the-shoulder sage green dress.
The outlet further dished that the blushing bride wore four different Oscar de la Renta bridal looks during her and Finneas' wedding weekend.
For the couple's official ceremony, Claudia wore a silk ivory gown complete with a drop-waist bodice and a structured, pleated skirt along with a draped, pleated scarf neckpiece.
More viral photos from the outdoor event showed Justin and Hailey Bieber, Kristen Bell, Dax Shepard, and Jason Sudeikis also in attendance, Page Six reported.
Finneas popped the question to his longtime girlfriend, whom he first met through a dating app, last September after dating for seven years.
It's no surprise that the Happier Than Ever singer officiated her brother's wedding, as the siblings have a very tight bond.
Billie has hailed Finneas as her "best friend forever," while the songwriter has come to his sister's defense several times.