"The Fabulist" host Kristin Cavallari welcomed her second child in May, a baby boy named Jaxon, and finally shared the first snap of him on Monday! Click here to see the adorable new addition to the Cutler family!

"Speaking of Jax, here is my precious little peanut," she captioned it.

The blonde starlet is already almost back to her pre-baby weight, and she recently spilled her secrets to E! News.

"I started working out when Jax was three weeks old," Cavallari revealed.

"I've been working out four to five times a week for 30 to 45 minutes at home, doing tons of leg work like squats, lunges and lifting weights."

She even plans on stepping up her already impressive regimen.

"I want to start Pilates again to focus on my core. I'll probably get back into it in the next couple weeks," the reality star said.

She added, "I'm still a couple of pounds away from my pre-pregnancy weight, but it took a solid three months with Camden and I think it will be the same this time."

When asked if she was using a special diet to help slim down, the former MTV star replied, "No, my diet is always the same. I don't eat any toxic chemicals and I try to eat organic as often as possible.''

Cavallari recently revealed her sons get along great and have a "cute" bond.

"Cam is really cute with Jax. He gives him kisses and holds his hand," the blonde gushed.

She continued, ''We just potty-trained Camden which we're really excited about! He's also starting to talk, which is hilarious and a ton of fun. Jax is getting close to holding his head up on his own.''

How adorable is the new baby? Let us know your thoughts in the comments section below.