Katy Perry Fangirls Hard Over Mariah Carey in Las Vegas

by Antoinette Bueno 1:20 PM PDT, July 20, 2015
Photo: Instagram

Taylor Swift's not the only one with superstar friends.

Katy Perry recently made her love for the one and only Mariah Carey known, taking in one of the 45-year-old legend's shows at Caesars Palace in Las Vegas. Mariah's currently doing her first-ever residency ever in Sin City.

Just how much of a fan is Katy? She declared herself a member of the "lambily," the nickname for Mariah's dedicated fandom. Mariah has long referred to her fans as "lambs."

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"Lambily 4lyfe," Katy Instagrammed on Sunday alongside a huge poster of the "Infinity" singer.

The 30-year-old "Dark Horse" singer also shared this video of the two ladies posing for pictures together, Katy in a dangerously low-cut dress and a furry pink shawl, while Mariah looked slim in a slinky black sequin gown.

And Katy clearly had no shame fangirling front-row at the show, as evidenced by this video of her taping Maiah on her phone and reaching out for her hand, though obviously, Mariah missed her.

But is this perhaps Katy's way to bury the hatchet? Some fans saw Katy's comments about Mariah during her appearance on Live on Sunrise last March as a thinly veiled diss.

"Well, she's fabulous for a throwback," Katy said about Mariah. "We love 'Fantasy.' And 'Honey,' I love 'Honey.' I sang all those songs growing up --her with Boyz II Men in the studio, 'One Sweet Day' with her little dog. Oh my God I love that."

WATCH: Is Katy Perry Taking More Swipes at 'Sweetheart' Taylor Swift?

ET actually caught up with Katy in May, when she gave her opinion on more controversial superstars -- the Kardashians. "The Kardashians, in my book, are completely valid," she said. Watch below: