Cook gave birth to the couple's second child on Saturday.
Rachel Leigh Cook and her husband, actor Daniel Gillies, welcomed their second child on Saturday.
E! News reports the baby boy, named Theodore Vigo Sullivan Gillies, was born at 5 a.m. in a Los Angeles area hospital, weighing 8 pounds, 14 ounces.
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This is the second child for the She’s All That star and her husband -- best known for his work on The Originals -- who tied the knot in 2004.
The couple also have a 1-year-old daughter, Charlotte Easton, born in September 2013.
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Congrats to the happy couple!
Check out the video below for a look at some of the best celebrity pregnancy announcements.