She gave birth to her fourth child just two weeks ago, but Kim Zolciak is apparently bouncing right back.

The Real Housewives of Atlanta star, 34, welcomed son Kash Kade Biermann Aug. 15 with husband Kroy Biermann. But by Sept. 1, Zolciak's post-baby body was looking seriously svelte.

PHOTOS: Real Housewives' bikini bods

Her daughter Brielle, 15, Tweeted a gasp-inducing pic of her reality star mom in a long, tight black dress and quipped what everyone else was thinking.

"Seriously . . . who looks like this after 2 weeks of having a baby?"

PHOTOS: Biggest Housewives brawls ever

No word yet on how Zolciak -- who's admitted to hating exercise on Real Housewives -- is dropping the pounds. Kash Kade joins big brother KJ Biermann, 15 months, plus Brielle and Ariana, 9, the Bravo star's daughters from a previous relationship.

VIDEO: See Kim without her wig!

Zolciak and Atlanta Falcons player Kroy, 26, wed in Nov. 11, 2011 in a wedding taped for their Bravo spinoff Don't Be Tardy for the Wedding.

This article originally appeared on Kim Zolciak Unveils Skinny Bod 2 Weeks After Giving Birth to Son