Bell and her husband, Adam Beason, are already the parents of a 7-year-old daughter, Gemma.
Their son was born Saturday morning, and weighed in at 7 pounds, 7 ounces, Bell's publicist told People.com exclusively.
The actress is best known for her work on TV's "JAG" and "Army Wives."
Beason is a film and TV production assistant and occasional actor.
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