Happy birthday, Paris Hilton!

The former Simple Life star turned 36 years old yesterday, and she celebrated by posting an epic throwback photo of her with her friend Kim Kardashian’s momager Kris Jenner — and the snap is full of early 00s nostalgia.

“Celebrating my 21st birthday at #Studio54 with [Kris Jenner],” Paris wrote in the caption, adding the hashtag “#BirthdayMemories.”

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Paris and Kris’ daughter Kim were once best friends, and Kim even got her start in reality TV on Paris’ hit series The Simple Life. The pals had a little bit of a falling out, but they’ve recently reunited at Kris' Christmas party last December. Kim also broke her social media silence following her horrifying robbery in Paris last fall when she followed the socialite on Instagram.

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It seems like even though they’re not quite best friends again, the pair is still friendly. Kim even gave Paris a birthday shoutout on Twitter and she wore her hair blonde — paying homage to Paris’ signature platinum locks.

“Today’s vibes channeling Paris! Happy birthday [Paris Hilton]. Can’t wait to celebrate with you soon!” the 36-year-old tweeted.

Scroll through the gallery below to see all of Paris and Kim’s throwback BFF moments!