She better stock up on those caffeine pills!

Elizabeth Berkley -- aka Bayside High's overcommitted activist Jessie Spano -- became a mom July 20, Us Weekly has learned. "I am moved to share the birth of our new baby boy, Sky Cole Lauren," she tweeted. "Thank you for your beautiful wishes and blessings. We are grateful!"

This is the first child for Berkley amd husband Greg Lauren; they have been married since November 2003.

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In March, Berkley, 40, debuted her growing baby bump, and shared her and Lauren's happy news with TMZ.

"In life there are moments you cherish forever, and this is one of them," the actress/author gushed.

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Berkley isn't the only Saved By the Bell alum to have become a parent since the show went off the air in the early '90s; Mark-Paul Gosselaar (Zack Morris), Tiffani Thiessen (Kelly Kapowski), Lark Voorhies (Lisa Turtle) and Mario Lopez (A.C. Slater) have all started families of their own within the last decade.

This article originally appeared on Elizabeth Berkley Gives Birth to Son Sky Cole!