Jessica Alba and Cash Warren Welcome Son Hayes Alba

Jessica Alba announced her third child on the way in July, revealing in October that she and husband Cash Warren would be expecting their first son

Cash Warren is no longer the lone male in his and Jessica Alba's household!

The spouses of nine years welcomed their third child and first son, Hayes Alba Warren, on Sunday, Dec. 31, Alba announced on Instagram Monday alongside the first photo of her baby boy shared to social media.

The newest member of the family joins Alba and Warren's two daughters: Haven Garner, 6, and Honor Marie, 9½.

"Hayes Alba Warren 12/31/17 Best gift to ring in the New Year!!" wrote the actress. "Cash and I feel so blessed. Haven and Honor are already obsessed with their new baby bro. 👶🏽💙 #familyof5"

Warren chimed in on Instagram too, sharing a photo of himself gazing down at his son alongside a beautiful message that read, "Hayes Alba Warren: You sure know how to ring in the new year! You showed up a few days early but we couldn't be any happier."

"Your Mamma is the strongest woman I know … you're so lucky to have her by your side," he added. "You have two amazing sisters who already adore you and I know you'll be thankful to have them guide the way."

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Warren continued in his post, "On your first day of life, I promise to love you, to cherish you, and to provide you with a sandbox full of dreams to explore. Welcome to the family my sweet baby Hayes! 12/31/2017."

Alba, 36, first announced she was expecting in July, sharing a cute Boomerang of Honor, Haven and herself holding up huge "1," "2" and "3" balloons, respectively.

"@cash_warren and I are officially going to be outnumbered #babyonboard #herewegoagain 👶🏼🤰🏽#blessed🙏," she captioned the post.

In late October, the actress and Honest Company co-founder revealed in another cute clip with her daughters that the baby on the way was a boy, showing the girls pulling on a string to release blue confetti from a suspended box.

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Alba has been open about the excitement she and Warren, 38, feel about adding a little boy to their family. During a late-October visit to by The Rachael Ray Show, the Dark Angel alum joked she was looking forward to having "someone to love me more."

"When [Cash] comes home, [Haven and Honor are] like, 'Daddy!' It's like a party," she explained. "When I come home, they're like, 'Oh, hey Mom.' I'm like, 'I do everything for you! I cook, I do all the things!' "

Earlier that month, the star said on The Tonight Show Starring Jimmy Fallon that the family was "super stoked" and that having a son was "gonna be a whole situation."

2017 Baby2Baby Gala - Arrivals
Jon Kopaloff/FilmMagic

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In early November, Alba debuted a line of Honest Company seasonal diaper prints for winter, saying in the accompanying reveal video, "What's so exciting about this winter diaper reveal is that this will be the diaper [print] that the little baby in my tummy will be wearing."

And although the new baby's sex is a nice bonus, what Alba was most looking forward to about caring for an infant one more time has everything to do with those first moments of new motherhood.

"Cuddling!" she told PEOPLE in August of her most-anticipated activity once her newborn arrived. "Cuddling babies are the best."

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