Congratulations, Rose Byrne and Bobby Cannavale!

The couple are proud parents to a new baby boy — and the name they chose for their son is the cutest!

During a Friday, Feb. 5 appearance on The Late Show with Stephen Colbert, Bobby, 45, revealed his "beautiful" son was born on Monday, Feb. 1 and he and Rose, 36, have named him Rocco.

rose byrne pregnant and bobby cannavale nove 2015 getty

Rose and Bobby in November 2015.

"You know, I didn't do anything… and I'm so tired," the Boardwalk Empire star joked to host Stephen Colbert. "I think I've gained 28 pounds since Monday."

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After months of speculation, sources close to Rose and Bobby — who have been dating since 2012 — confirmed the longtime couple were expecting a baby together in October 2015. This is the first child for Rose and the second for Bobby, who has a 20-year-old son, Jake, from his previous marriage to Jenny Lumet.