Darbo was born Patricia Davidson in Jacksonville, Florida, the daughter of Patricia, a restaurant hostess, and "Chubby" Davidson, a nightclub manager. She grew up in Atlanta, Georgia, and was raised by her stepfather, who taught her to reach for her dreams no matter what obstacles she might face (he was a dwarf, standing only 4 ft. 2 in. tall, but was the personal secretary for the owner of the Atlanta Braves).
Darbo went on to study theater at Georgia Southern University in Statesboro, Georgia, graduating in 1970, and pursued additional study at the Atlanta School of Drama. She has been married to director Rolf Darbo since 1973. Darbo first went into fame as Penny Baker on Step by Step (1992-1993) and famous as Nancy Wesley on the NBC soap opera Days of our Lives from 1998 to 2003 and made several appearances in 2004 and 2005.
Darbo currently appears in advertisements for BellSouth in the Atlanta area. She currently resides with her husband in suburban Atlanta.