Alec and Hilaria Baldwin have welcomed a baby girl.

The 29-year-old yoga instructor checked into New York's Mount Sinai hospital on Friday where she gave birth to the couple's first child, whom they named Carmen.

"We are overjoyed to announce the birth of our daughter Carmen Gabriela. She is absolutely perfect (sic)," Hilaria wrote on Twitter.

Alec's daughter Ireland, 17, from his marriage to Kim Basinger, also took to Twitter to share her joy: "Welcome to the world, Carmen! I'm a f***ing sister! The best big sister!! Love you so much (sic)."

A source told the New York Daily News, "Alec is overjoyed."

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