At Kelly Clarkson’s concert Wednesday night, she surprised her fans with a cover song in honor of Demi Lovato’s 23rd birthday.

Teasing the song, Clarkson said, “It’s one of my girl’s birthdays tomorrow. And when I say my girl, I mean Demi Lovato. It’s Demi’s birthday tomorrow and she’s always been so supportive and so cool. To see a kid that used to go to my shows have this huge, lustrous career — she’s just killin’ it. I thought I would, for her birthday, sing her new single Cool For The Summer.”

and Demi FREAKED OUT

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