"We are so pleased to introduce you to our new baby, Leonardo Angel Charles Baldwin," Hilaria, 32, captioned the sweet image of herself in a hospital bed cuddling the family's new bundle of joy. "It was such a special day bringing him into this world."
The Oscar-nominated actor, 58, also tweeted out a few details about his son's birth: "Leonardo Angel Charles, September 12, 6:51pm, New York City," he shared along with a link to his wife's Instagram photo.
The celebrity couple — who married in June 2012 — are also the parents of Carmen, 3, and Rafael, 14 months. The 30 Rock alum is also dad of model Ireland Baldwin, 20, whom he shares with ex-wife Kim Basinger.
In March, the Baldwins also took to social media to share the news that they were expecting their third child together, less than a year after welcoming little Rafael.
"Ireland, Carmen, Rafael, Alec, and I are excited to share with you that we are going to have another addition to our family," Hilaria captioned an Instagram photo of the couple kissing. "A little boy coming this fall."
The Yoga Vida cofounder told Us Weekly exclusively in June 2015, shortly after giving birth to Rafael, that her daughter is already a great older sibling.
"She wants to kiss him, hold him, sing to him and feed him food she can't eat," the limber mom of three, who often shares photos of herself on social media in incredible yoga poses, told Us at the time. "She's a good big sister."
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