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/ Source: TODAY
By Gina Vivinetto

Kim Zolciak-Biermann is catching heat for sharing a photo of her 6-year-old son, Kash, sitting in a car seat.

The former "Real Housewives of Atlanta" star, 40, took to Instagram on Tuesday to share a pic of Kash riding to school in a backless booster seat. "My baby @kashbiermann on the way to school this morning! He is such a BIG BOY he is only 6," she captioned it, adding, "He melts me. His heart is unreal #HairKing."

Some of Zolciak-Biermann's followers were quick to comment that, indeed, Kash is a "BIG BOY" — too big for his car seat.

"Omg he’s too big for that booster!" one fan wrote.

"Not safe," wrote another.

"Look like he should be in the driver seat," a third joked.

As more fans fretted that Kash was "way over the weight limit" for a booster, the mom of six took the criticism in stride, even responding to some comments.

"I’ll keep them in one until they are 18," she joked.

Other fans chimed in to say that Zolciak-Biermann was exactly right for keeping her son in a booster.

"So happy to see he is still in a booster!! More people should educate themselves on car seat and booster seat safety and requirements!" one shared.

The commotion prompted Zolciak-Biermann to share guidelines on how parents can determine for themselves when kids have outgrown a car seat.

"Ya’ll know I don’t play when it comes to my babies," she wrote next to a pic of a few rules she posted in her Instagram Story.

Zolciak-Biermann also shared a helpful video for the busybodies that showed markings on a wall where she keeps track of her kids' heights.

Kash, for the record, is 4 feet, 5 inches tall.

In its car seat guidelines, the American Academy of Pediatrics advises that once kids are facing forward, they should use a forward-facing car safety seat with a harness for as long as possible. But once they outgrow those seats, they should switch to a "a belt-positioning booster seat" until they can safely use a vehicle's regular lap and shoulder seat belt.

That happens, the AAP says, around the time a child is 4 feet, 9 inches in height.

In other words, Zolciak-Biermann may be catching flak, but she's got her car seat facts correct.