In honour of her upcoming milestone birthday on April 24, Kelly Clarkson has already begun celebrating turning 40 all week long on “The Kelly Clarkson Show”.

On Friday’s episode of the 80s-themed week, which paid tribute to the “best” decade since Clarkson was born in 1982, the TV host’s crew threw her a birthday surprise party. The “Because of You” singer had “no clue” what producers had planned for the show, including which guests would appear.

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Clarkson’s first surprise was her childhood best friend, whom she was overjoyed and shocked to see. The two, who’ve known each other since the third grade, reminisced on working their first job together at a local movie theatre and recalled both getting in trouble at school, so much so that they were no longer allowed to be in the same classroom together.

After joking about being “so old,” Clarkson was interrupted by Machine Gun Kelly who suddenly walked through the studio doors, surprising the “birthday girl.”

Machine Gun Kelly and Kelly Clarkson
Machine Gun Kelly and Kelly Clarkson — Photo: Weiss Eubanks/NBCUniversal

The “At My Best” singer, who woke up 15 minutes before appearing on the show, was also celebrating his birthday that same day (April 22). He surprised Clarkson with the all-female mariachi band, Mariachi Bonitas, along with a queso fountain and margaritas, which he and his Taurus sister indulged in.

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Just when Clarkson thought her final surprise was a visit from “the star of one of [her] favourite shows on television,” a.k.a “The Rookie”‘s Nathan Fillion, the actor took it upon himself to bring in four more surprises, his co-stars Mekia Cox, Alyssa Diaz, Melissa O’Neil and Eric Winter.

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Nathan Fillion, Michael Ealy, Rick Astley and Kelly Clarkson
Nathan Fillion, Michael Ealy, Rick Astley and Kelly Clarkson — Photo: Weiss Eubanks/NBCUniversal

Watch the video below to see which “Rookie” star’s party Barbra Streisand showed up to and how Fillion likes to prank his co-stars on set using banana peels.

Elsewhere during the birthday episode, Clarkson was also surprised by actor Michael Ealy and singer-songwriter Rick Astley, who sang a medley of his 80s hits including “Never Gonna Give You Up.”

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