Too cute!

Three weeks after Bobby Cannavale and his longtime girlfriend, Rose Byrne, welcomed their first child, a baby boy named Rocco, the actor has opened up about his newborn son — and confessed the couple is in total "bliss" with their new addition!

“We’re just really, really over the moon,” Bobby, 45, said in a recent appearance on The Late Show with Stephen Colbert, according to People. “We’re in bliss right now.”

rose byrne pregnant and bobby cannavale nove 2015 getty

Rose and Bobby in November 2015.

The Annie star additionally revealed Rose, 36, is an "incredible" mother to their baby son. “She’s incredible — she’s what you’d think she’d be. She’s beautiful and wonderful and he’s a beautiful boy," he said.

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The couple — who began dating in 2012 — welcomed Rocco on Monday, Feb. 1. After months of speculation, sources close to Rose and Bobby confirmed the duo 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.