It was a family affair when Carrie Underwood wrapped the summer leg of her Reflection: Las Vegas residency on Saturday night (July 1). The singer's mom Carole and older sisters Shanna and Stephanie came to Vegas for the occasion, and they celebrated the special family moment by getting matching tattoos.

That's right -- all four of the Underwood girls left town with the same new tat: A delicate, gracefully stylized outline of a heart. Underwood got hers on her right foot, while the other three women chose to put their ink on their wrists.

A social media post from the star shows off the new tattoos, and expresses Underwood's shock that her mom -- who's in her mid-'70s -- was game for the fun bonding exercise. Not only was Carole up for it, but according to the caption of the post, it was her idea.

"When your 74-year-old mother asks you and your sisters to get matching tattoos with her in Vegas, the only questions are 'what?' and 'where?'" Underwood writes. "I never would've thought I'd see the day that Mama Carole would be gettin' some ink!"

But sure enough, she did: One photo shows Carole smiling in the tattoo artist's chair, while other pictures in the slideshow show all four women posing together in the studio. In another snapshot, it's Underwood's turn to get tattooed -- and she shows off her new ink in a close-up shot of her foot.

Though it might've been Carole's first tattoo, it certainly wasn't Underwood's: In fact, the country star has been on a little bit of a tattoo kick recently. In May, she shared photos of a delicate flower she got inked on her forearm during a girl's trip to Destin, Fla. with her sisters-in-law.

Underwood's summer leg of her Vegas residency began in mid-June, and she's currently on a break from the show, but she'll return for more dates in September. The Reflection residency will wrap for the year in early December.

See Country Stars With Their Moms

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