Cronin was born on October 10, 1939, to Frank and Elizabeth Lewis. She had a son, Christopher, and a daughter, Jennifer. She maintained a residence in Oak Park, Illinois, for twenty years.
Prior to her move to Los Angeles in 1990, Cronin worked thirty-five years of her career in theatre based in Chicago. In 1987, she won the Joseph Jefferson Award for Best Actress for her performance as Mrs. Hardcastle in She Stoops to Conquer at the Court Theatre. In 1980, she also appeared on Broadway in Passione.
On October 26, 1992, Cronin died of cancer at the age of 53 at Northwestern Memorial Hospital.
