Olivia Munn and John Mulaney Introduce Their Newborn Baby Boy Malcolm Hiệp: 'Very in Love'

Roy Rochlin/Getty; Jon Kopaloff/Getty John Mulaney, Olivia Munn

John Mulaney and Olivia Munn are introducing the world to their baby boy.

The Newsroom alum, 41, and the comedian, 39, shared sweet photos of their newborn son, Malcolm Hiệp Mulaney, on Friday via their Instagram accounts.

"My Golden Ox baby. Malcolm Hiệp Mulaney. Happy Holidays," Munn captioned her post. Wrote Mulaney on a snap of his son sleeping: "Meet Malcolm Hiệp Mulaney. He has his whole life ahead of him. He hasn't even tried seltzer yet. I'm very in love with him and his whole deal. Happy Holidays."

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Mulaney revealed that they were expecting on Late Night with Seth Meyers in September. "I got into this relationship that's been really beautiful with someone incredible ... And we're having a baby together," he told host Seth Meyers at the time.

"Olivia and this baby have helped save me from myself in this early journey out of recovery," Mulaney added. He checked himself into rehab last December following a decades-long battle with addiction.

Munn told PEOPLE in September that she's "really excited" to become a mom, adding that they were "still deciding" whether to find out the baby's sex before the delivery.

"I've been getting a lot of rest and eating the right foods. And my friends have been giving me some great advice. That's been keeping me sane!" she shared, adding: "What's helped me the most is when friends tell me not to compare myself to other pregnant women."

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"My mom crochets and knits a lot of stuff," added Munn. "She makes little rattles or stuffed animal toys already. This is still a new experience for me so to see my mom excited makes it feel a lot more real! I'm really excited."