Graduated from New York University's Tisch School of the Arts undergraduate drama program 
Daughter, Maeve Elsbeth Erbe Kinney(born October 26, 1995).
Became a member of the Steppenwolf Theatre Company's ensemble in Chicago in 1993, which her husband Terry Kinney co-founded.
Son, Carson Lincoln Kinney, born October 15, 2003
Incorporated her real-life pregnancy into her "Law & Order: Criminal Intent" (2001) character, Detective Alexandra Eames, by stating that she was being a surrogate mother for her infertile sister.
The oldest of three children; her mother, Elisabeth Magnarelli, was a vice president of a Boston management firm, and her father, Dr. Richard Erbe, is an internist subspecialized as a medical geneticist.
An ensemble member of the Atlantic Theater Company in New York City.
In Sept 2011, obsessed fan Charles Nagel 37, was sentenced by a New York judge to five years probation for stalking and harassing Kathryn Erbe and her family.