Kristin Cavallari stepped out with newborn son Jax and revealed her post-baby body on June 12, just one month after giving birth Credit: Splash News

Lookin' good, girl! Kristin Cavallari revealed her slimmed-down-again figure as she stepped out for some fresh air with newborn son Jax in the suburbs of Chicago on Thursday, June 12.

The Hills alum, 27, glowed as she took a walk with her precious cargo, but kept her baby's face hidden underneath a blanket as he rested in his stroller. She wore a felt hat, green cut-off shorts and a beige long-sleeve shirt, while carrying his little booties in her hand. She also wore sandals from her Chinese Laundry collection.

Cavallari and husband Jay Cutler, 30, welcomed their second child last month, and announced the news via Instagram.

"Welcome Jaxon Wyatt Cutler. 7lbs 11oz 5/7/14," Cavallari wrote. Alongside the caption, she shared a sweet snapshot of his shoes—the same ones she carried on her walk—and a blue-and-white striped hat.

Cavallari and the Chicago Bears quarterback wed in June 2013. Baby boy Jax now joins big brother Camden, 20 months.