Mark-Paul Gosselaar and Wife Welcome Baby Girl Lachlyn

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Mark-Paul Gosselaar and his wife, Catriona McGinn, welcomed their new baby daughter on Tuesday!

On Wednesday, the former Saved by the Bell star took to Twitter to announce the big news, tweeting, "So in love with our new baby girl, Lachlyn! Born last night 2/17 Mum and baby are healthy and happy. 2 boys, 2 girls, too perfect!"

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Aside from sharing his baby's name, Gosselaar also Instagrammed one of the cutest baby pics ever, captioning the adorable photo of his sleeping baby, "She's a 'mouth-breather' like her Daddy. My sweet little angel."

The couple announced they were expecting in December.

This is Gosselaar's second child with McGinn after they welcomed their son, Dekker Edward, in October 2013. Gosselaar has two other children, 10-year-old son Michael and 8-year-old daughter Ava, with his ex-wife, Lisa Ann Russell.

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Congrats to the happy family!

Check out the video below for a look at some of the greatest celebrity baby announcements from 2014.