Duff and husband Mike Comrie are the proud parents of a healthy, 7-pound, 6-oz baby boy named Luca Cruz Comrie.
The 24-year-old tweeted, "We are overjoyed and feel like the luckiest parents in the world."
Duff and Comrie, 31, a retired hockey player, married in August 2010.
Stars Who Recently Had a BabyStars Who Recently Had a Baby
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