Tiffani, who played cheerleader Kelly Kapowski in the 90s show, announced the happy news via Instagram last night after welcoming her second child, Holt, with husband Brady Smith.
Sharing a photo of her daughter Harper Renn and her newborn son, Tiffani revealed: "Yesterday Harper got a little brother! We are so excited to introduce Holt Fisher Smith.
"Our perfect sweet little man. #weareblessed #familyoffour."
In the snap, Harper beams as she holds her little baby brother, who is sleeping, in her arms.
Tiffani said back in January that Harper was excited to be a big sister, saying: "Harper could not be more thrilled to have a sibling and a playmate."
And Harper had even been begging her parents to have another child, with Tiffani revealing in December last year: "My daughter is more pressure than anyone else that I ever get. She wants a sibling so badly!"
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