Appearing on the Late Show With David Letterman Jan. 2, the Zero Dark Thirty actor, 33, opened up about their firstborn, Jack. (The parents welcomed the little boy prematurely in August 2012.)
"Oh, God, he is just . . . he's amazing. I love him so much," Pratt gushed. "He's just a ball of joy. He's terrific."
Said Pratt, "He was born nine weeks premature, so we spent a month in the intensive care unit with him. But he's totally healthy now. He is just so perfect and I love him so much."
With Pratt busy promoting Zero Dark Thirty and shooting new episodes of NBC's Parks and Recreation, his 36-year-old wife has had her hands full at home. Unfortunately, that doesn't leave much time for the What's Your Number? actress to hit the gym.
Luckily, Faris isn't feeling any pressure to get her post-baby body back. "I have the sweetest husband," she said in December. "He makes me feel good at any weight. In fact, I kinda think that he likes it when my butt is a little bit bigger!"
This article originally appeared on Usmagazine.com: Chris Pratt: My Son Jack With Anna Faris Is "Totally Healthy" After Premature Birth