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Nick and Vanessa Lachey's brood has officially grown.

The former 98 Degrees frontman and his wife welcomed their daughter Brooklyn Elisabeth Lachey on Jan. 5, Vanessa announced on her website. It's the second child for couple.

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"She's HERE!!!! Nick, Camden and I are SO excited to announce the birth of our sweet, beautiful baby girl," Vanessa wrote on her website with a photo of what appeared to be mama holding baby Brooklyn's hand.

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Brooklyn came in weighing 7 lbs, 15 oz. and measured 21 inches long, Vanessa wrote, adding the baby girl "has already won over all of our hearts."

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She continues, "I have been dreaming of this moment for as long as I can remember, the day I was going to meet my little girl. A friend recently told me how magical today was going to be because it's the day I would meet my best friend. I can't even begin to tell you how it felt to hold her in my arms for the very first time. Mommy, Daddy and big brother Cam love you so much already, Brooklyn!"

Vanessa's pregnancy seemed to go rather smoothly, as she spent her pregnancy chasing around the couple's 2-year-old toddler and showing off her baby bump on multiple occasions -- just before Christmas, the then family-of-three posed for a Christmas card that showed Nick kissing his wife's belly.

Motherhood, Nick said, has actually brought out the best in his wife, and he sees her in a new, sexy light.

"My wife's maternal side is a new dynamic to her personality," Nick Lachey told Parents magazine after the birth of Cameron. "It's definitely made her even sexier."