The actress and husband Ben Affleck welcomed their second child on Tuesday, a sister for three-year-old Violet.
"I talked to her and she's doing great," he told PopWrap. "It was a much easier birth, which I guess is true of most second births - they're easier. She sounded fantastic. I'm very excited.
"I think that the chances it'll be an attractive child are very good. I just marvel at how they're being brought up. What a wonderful mother Jennifer is, and what a joy it is to be around that family."
The Hollywood couple, who married in 2005, have yet to reveal the newborn's name.