Monaghan was born in Winthrop, Iowa, the daughter of Sharon Monaghan (who ran a day care center in the family's home), and Bob Monaghan (a factory worker and part time farmer). She has two older brothers, Bob and John and her family frequently fostered and adopted children. She graduated from East Buchanan High School Class of 1994, where she was the class president and acted in a few plays. After Read more...

Monaghan's first notable though minor parts were in episodes of Young Americans, (in which she appeared twice), and Law & Order: Special Victims Unit, both in 2001. Monaghan made her big screen debut that year in the small role of Henrietta in the movie Perfume. This was followed by another small role in Unfaithful in 2002. She expanded her résumé by doing commercials for products such Read more...

She met Australian graphic artist Peter White at a party in 2000 and they were married in August 2005. They live in New York City and are expecting their first child in late fall of 2008.