Billie Eilish is celebrating a very special birthday, that being of her close friend Claudia Sulewski, aka her brother Finneas O'Connell's longtime girlfriend.
The singer, 22, has been friends with the actress and YouTuber, who turned 28 on February 19, for over five years, having first met when she started dating Finneas, 26.
The pair have been together since 2018 and have even worked together on some of the songwriter's solo musical projects (billed under FINNEAS), and he's been a part of her online content frequently.
Billie took to her Instagram Stories to share sweet tributes to Claudia, adding a snap of hers alongside which read: "birthday cloobi doobi."
She also included a throwback photo from a night in the pool, with Billie's then blonde locks in an updo as she clicked a selfie wearing a black swimsuit and a gold chain. Claudia, meanwhile, was even more submerged, and Billie captioned the snap: "Lucky 2 know u."
Finneas, meanwhile, took to his Instagram page with a sweet photo of theirs at home together, writing alongside it: "Happy birthday to my most precious Claudia who has made the world a better, brighter place since she got here – so lucky you were born when you were, so lucky to be around you."
After a birthday celebration at Girl & the Goat in LA with Finneas and friends, she wrote alongside a photo compilation on her social media: "Thank you for making yesterday feel so special.
"Every cell in my body has been ricocheting with gratitude, love, ardor and the silliest amount of excitement… have never felt so at peace in my entire being, it truly becomes clearer each and every year! Thank you @casamigos! So many sweet memories and cocktails were made last night hehe."
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The I Love My Dad star has been a fixture of several red carpets alongside her boyfriend, most recently at the 66th Grammy Awards and the 81st Golden Globes (where Billie and Finneas picked up trophies for their contribution to the Barbie soundtrack, "What Was I Made For?").
While Claudia and Billie enjoy a close relationship, the singer has not featured on her YouTube content often, and after several fans questioned why, Claudia responded in a YouTube Q&A back in 2020.
"I get a lot of comments from you guys asking why I don't put Billie in my videos," she started, reasoning that it was because of her huge fame, and she didn't want to attract unwanted attention.
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"Billie is very famous, obviously, to the point where there's anything about her, or a split second of her, in one of my videos, it gets reposted and recorded, just shared everywhere.
"And I don't want or need that kind of attention on here, because I don't want people to think that that's what they're gonna get when they come [on my channel]," she continued.
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"If you're here, this is what you came for, this is what you're getting. So to answer that question, it is one hundred percent a conscious decision and choice."
Claudia explained also that not every moment in her life was recorded and put online, saying that it was "a very obvious statement."
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