Duff tweeted the happy news on Thursday, writing:
“Welcome to the World Luca Cruz Comrie! Tuesday evening, we became proud parents of a healthy 7 pound 6 ounce beautiful boy. We are overjoyed and feel like the luckiest parents in the world.”
Adding, “He is surrounded by so much love!! Mom and baby are both doing extremely well.”
Luca is the first child for the couple, who married in August 2010. Duff announced she was expecting in August 2011.
Congrats to the proud parents!