Molly Sims is officially a mom-of-three!

The 43-year-old model welcomed her third child, a baby boy named Grey Douglas Stuber, with husband Scott Stuber on Tuesday, Jan. 10, Molly confirmed via Instagram.

"Welcome to the world, Grey Douglas Stuber. 1.10.17. Words do not express how grateful and happy we are to have another piece of magic added to our little tribe! #Blessed?#TribeOf5," the star captioned the first photo of herself and her newborn baby boy.

Molly and her film producer hubby, Scott, 48, are already parents to two older kids, son Brooks, 4, and daughter Scarlett, 1. The couple — who previously tied the knot in September 2011 — announced they were expecting their third child in August 2016.

"Hey guys, I have a very special announcement… We are having Baby No. 3! We're so excited," Molly in a cute video posted to her YouTube page last summer.

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"We never expected it would happen, we didn't even know. This is such a true surprise, I think that's why I'm so emotional. He or she will be here before we know it," she continued.

Three months later, Molly posted another video to her YouTube page revealing the couple's unborn baby was a boy! "We're very excited," Molly began the clip, which also starred Brooks and Scarlett, 19 months. "We're having a boy! YAY!"

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"Brooks is really excited about having a baby boy. He's already named it Jack and the Bean Stalk-Batman, that's his full name. And it's been really sweet to see him so involved and kiss my belly," the star continued.

"When they told my husband that we were having a boy I swear I think he almost started crying, he was so happy," Molly added. "So, that's it, it's happening — we're having a boy!"

Congrats to Molly and Scott on their adorable new addition!