Biermann, 27, and Zolciak, 35, have been married since November 2011 and have had two sons together, Kroy Jr. and Kash Kade.
During an interview with E! news, the former "Real Housewives of Atlanta" star opened up about the relationship between her husband and her two daughters.
"I don't know if I could love anybody else's children as much as Kroy loves the girls," she said of Biermann. "I just don't know if I have it in me."
The NFL star turned family man added that his life has changed significantly since he began sharing it with Zolciak and the kids, and pointed out that his family is his new priority.
"Before Kim and before the girls and before the boys, I lived a pretty regimented life," Biermann said. "I'd wake up, eat breakfast, go to work, come home -- it was pretty normal. Now, my house isn't going to be as clean as it was before, but it's not important. Those things are not important and it's all about prioritizing and understanding."
As for how the girls feel about their now-official father, Zolciak explained they approved "almost immediately."
"My daughters are very smart…I didn't bring everyone around them," the reality star explained of her life before Biermann. "The relationships I had were long-term, but sometimes my daughters would notice that the person I was dating, they were doing things to kind of win my daughters' over to get to the mom—it wasn't genuine. And my girls can see right through that crap. So with Kroy, it was just real…It worked from the very very beginning."
Zolciak is currently pregnant with the pair's fifth child.