The 24-year-old made the official announcement on Twitter Thursday afternoon saying, "Welcome to the world Luca Cruz Comrie! Tuesday evening we became proud parents of a healthy 7 pound 6 ounce beautiful boy."
It's the first child for the former Disney star and her NHL star hubby, Mike Comrie.
"We are overjoyed and feel like the luckiest parents in the world," Hilary wrote.
"He is surrounded by so much love!! Mom and baby are both doing extremely well."
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