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According to OK! magazine, JAMIE LYNN SPEARS has just given birth to a baby girl.

"Both mom and baby are healthy and happy," a rep for Jamie Lynn tells OK! exclusively. "They are surrounded by their close relatives, including Jamie Lynn's older sister BRITNEY, mother LYNNE, father JAMIE and brother BRYAN."

The 17-year-old delivered at 9:33 this morning in a hospital near her new home in Liberty, Mississippi, the mag reports.

Little MADDIE BRIANN, weighing in at seven pounds 11 ounces, is the first child for the "Zoey 101" star and fiancé CASEY ALDRIDGE.

Just yesterday, Britney flew in to be with her family for the special delivery.