Actor Mark-Paul Gosselaar is a dad again after his wife Catriona gave birth to the star's fourth kid on Tuesday night (17Feb15).

Little Lachlyn is the couple's second child together. Gosselaar also has two children, eight-year-old Ava Lorenn and Michael Charles, 10, from his first marriage to Lisa Ann Russell.

Announcing the news of his new arrival on Twitter.com, the actor writes, "So in love with our new baby girl, Lachlyn! Mum and baby are healthy and happy. 2 boys, 2 girls, too perfect!"

The couple's first child, Dekker, is 16 months old.

The Saved By the Bell star wed his second wife in 2012, a year after divorcing Russell.

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