Credit: Twitter Photo: Kristin Cavallari's Post-Baby Body

Not that we doubted it before, but Kristin Cavallari has some seriously good genes.

The new mom and former Dancing With the Stars contestant tweeted a new photo of her post-baby body that is bound to make some new mothers weep.

In the photo, The Hills starlet shows off her skinny body in shorts and a printed tank top.

“Girls night!! Yes at 6pm haha,” Kristin tweeted with the photo. Hey, moms need to party too, even if that means partying before sundown.

The 25-year-old star gave birth to her first child on August 1. That means that in roughly four weeks, KCav went from recovering mama to slim hottie. Grr, now we know why Lauren Conrad was jealous of her all the time!

Dancing With the Stars Season 15: All-Stars will premiere on Monday, September 24 at 8 p.m. ET/PT on ABC. Check out the full All-Stars cast list here.

Source: @KristinCav

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