Flea, the unmistakable funk-rock bassist of the Red Hot Chili Peppers, turned 60 on Sunday (Oct. 16). To celebrate, Paramore singer Hayley Williams led the audience at Austin City Limits Festival in singing "Happy Birthday" to the musician. Both bands played ACL 2022 on Sunday.

"I've loved you since I was 8 years old and it was really inappropriate," Williams ad-libbed among the more traditional "Happy Birthday to You" lyrics, as fan-captured footage from the concert shows. "Happy motherfucking birthday to Flea," she harmoniously added.

Watch the video down toward the bottom of this post.

The Red Hot Chili Peppers, including the prodigal guitarist John Frusciante, have staked a comeback of late with two new studio albums issued this year — April's Unlimited Love and this month's Return of the Dream Canteen. Get Red Hot Chili Peppers concert tickets here.

Paramore, the pop-punk favorites who will release the new album This Is Why next year, recently launched their first concert tour in four years. Get Paramore tickets here.

Paramore and Red Hot Chili Peppers shared top billing with three other headliners at the closing night of the ACL Fest on Sunday in Austin, Texas — the country-pop star Kacey Musgraves, the electronic musician Zhu and the hip-hop artist Lil Durk. At the show, Paramore also brought rising U.K. pop star PinkPantheress onstage to help sing their classic "Misery Business," as Stereogum reported.

Paramore's Hayley Williams Sings "Happy Birthday to You" to Red Hot Chili Peppers' Flea - Oct. 16, 2022

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