Big booty, baby! Kim Zolciak's fans are totally convinced the junk in her trunk is not natural and all thanks to a plastic surgeon. The buzz started after the Don't Be Tardy star shared a photo of herself and her husband, Kroy Biermann, on Instagram with her backside on full display. Watch the video above to see what fans are ogling over!

"Brazil butt lift without a doubt. She does not work out like she claims!! LOL," one person said. Another wrote, "I'd like the name of your fabulous doctor, please!!!" Kim has yet to address the recent rumors, but she did admit back in August 2016 to getting injections in her butt to eliminate cellulite — but the photo has since been deleted.

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Behind the scenes 😝

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The doctor responsible for doing the procedure? None other than Dr. Simon Ourian who has worked on Kim Kardashian, Khloé Kardashian, and several other members of the famous family. And he knows exactly what he's doing to get that perfect bubble butt!

"By carefully injecting tiny amounts of these semi-permanent fillers into individual cellulite dimples, I can detach the connective tissue (fascia) that causes cellulite and fill the indentations, resulting in a smoother skin surface," Dr. Ourian previously told Us Weekly. "Detaching the fascia and the small initial fill produce an immediate benefit and the collagen building qualities of the injections restore the underlying structure of the skin that continues to improve the skin's appearance over time."

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My happy place 🌊

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While Kim has kept quiet about any recent trips to see Dr. Ourian, it's clear that whatever he's doing or whatever he did, absolutely worked for this Bravo star. And she's totally down to show it off.

Kroy and Kim celebrated her 40th birthday with a family friendly bash and then traveled to an undisclosed location for a quick trip and a sultry photo shoot. Kim captioned one of the shots, "These last 48 hrs have been a dream! Party with family and friends, and now the beach for a short getaway #ThisIs40Baby #YouAreWhatYouThink."

So clearly, she thinks she looks hot AF and we don't blame her. She's one sexy mama and Kroy definitely doesn't disagree.