Kate Chastain's bundle of joy is Cassian Grantfinally here.

The Below Deck alum gave birth to her first child, a baby boy, she announced in an Instagram post on May 5. The Bravo star also revealed the little one's name, writing, "Hard Launch: Sullivan Cay."

In the accompanying photo, Chastain holds Sullivan in her arms in her hospital room not long after welcoming the little one. And it seems Sullivan is already a pro and taking selfies as he flashes a smirk while looking right at the camera.

The Bravolebrity's famous friends quickly took to the comments to congratulate her. "Awww congratulations," The Real Housewives of Beverly Hills' Garcelle Beauvais wrote, while her The Traitors co-star Ryan Lochte shared, "Soo happy for you."

The 40-year-old announced she was expecting in December 2022. "I am absolutely thrilled to become a mother," she revealed at the time. "It's something I've always hoped for so this is truly a dream come true!"

She later gushed "it's been the easiest pregnancy ever," noting that the experience made her feel "so lucky."

In January, Chastain got candid about her decision to raise her child as a single parent.

 "I'm fiercely independent," she admitted on the Jan, 24 episode of Page Six's Virtual Reali-Tea podcast. "I don't really love people's opinions being different than mine, and trying to make me go their way. So I really am so excited that I'll be able to do this exactly how I want to."

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