Kim Zolciak-Biermann's Sons KJ, 13, and Kash, 12, Look All Grown Up as They Tower Over Her in New Photo

Kim Zolciak-Biermann's eldest sons are all grown up!

On Sunday, March 30, the Real Housewives of Atlanta alum, 46, posted a picture of her two eldest sons, KJ, 13, and Kash, 12, on Instagram as she posed with them at an event.

In the photo, Kim stood in the middle of her boys as they towered over her.

She wrote in the caption that she "couldn't be more proud of my boys," before sharing a little update on what they've been up to lately.

"Football is their true passion," she continued. "They give it their all!! Early morning workouts, after school work outs, boats load of food, commitment, drive and a true love for the game. Makes me so happy."

In a nod to just how much her sons have grown, she added: "KJ is 13 and 6'1 🤩 Kash is 12 and 6'1🤩 (I'm 5'7 1/2 😜) 🙈."

"Omg how time flies!!! ❤️❤️," wrote Kim's former costar Shereé Whitfield in the comments section, while NeNe Leakes, who has had well-documented bad blood with Kim in the past, added, "OMGGGGG the boys are so big now! Growing fast 😍."

Kim shares KJ and Kash with her ex, former Atlanta Falcons linebacker, Kroy Biermann. The pair, who called it quits for the second time in August 2023, are still in the midst of their contentious divorce.

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The reality TV personality has two other children with the former NFL star, 39, son Kane and daughter Kaia, 11-year-old twins who were born 30 minutes apart in 2013.

She also has two daughters: 28-year-old Brielle, whose father's identity has never been made public, and Ariana, born in 2001, when Kim was still with her then-husband, Daniel Toce. Kim and Toce divorced in 2003. Kroy filed to adopt Brielle and Ariana shortly after the couple married in 2011, and they legally changed their last names when the adoption became final in July 2013.

With her kids growing up, Kim has been keeping as busy as ever. The former Bravo star will reportedly join the cast of Hulu's upcoming Got To Get Out, a reality competition show where former reality TV stars and media personalities live under one roof and work to get out of the house for a chance at $1 million. Spencer Pratt, Cynthia Bailey, Demi Burnett, Omarosa, Val Chmerkovskiy and Clare Crawley, among others, are set to star. Actor Simu Liu will star as host.

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Kim also revealed to TMZ on March 12 that she is dating a new man amid her ongoing divorce with Kroy. A source told PEOPLE that Kim's new beau is an "average Joe" who she met on Instagram.