Former Buffy The Vampire Slayer star Sarah Michelle, 35, gave birth to the couple's second child in Los Angeles this week.
The proud new parents said that they are "thrilled" about their new arrival, who hasn't been named yet.
A rep added: "Mother and baby are doing great."
Sarah and Freddie, 36, are already parents to three-year-old daughter Charlotte Grace.
The couple married in September 2002 after meeting on the set of the 1997 horror movie I Know What You Did Last Summer.
Congratulations Sarah and Freddie!
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