Jennifer Connelly and Paul Bettany welcome a baby girl
Connelly, 40, opted for a home water birth, according to People magazine.
"Everyone is healthy and doing well," said a statement released by her rep. "The family is very excited."
Agnes joins two brothers, Stellan, 7, and Connelly's son Kai, 13, from her relationship with David Dugan.
"Becoming a mother has made all the difference in terms of learning to take more responsibility for myself and my life," the actress told the Daily Mirror in 2009. "Parenthood changed the way I do everything."
As for Bettany, having a little girl might change things for him in a big way. The Brit, who married Connelly in 2003, admitted to Jimmy Fallon a few weeks ago that he didn't know the baby's gender but was worried about having a daughter.
"I'm really nervous because I'm a really overprotective father; I've got two boys, and now I'm wondering what it's going to be like if I have a girl. I'm gonna be crazy."
-- Emily Christianson
Photo: Jennifer Connelly and Paul Bettany. Credit: Stephen Lovekin / Getty Images