Who is Theresa Daly from Faithful Place: A Novel and what is their importance?

Theresa Daly is Rosie's mother. She was known as Tessie as a child, and she was very beautiful. She and Pa Mackey went out together, and the car apparently broke down, leaving them stranded overnight. Though they claimed that Tessie slept in the back seat and Pa in the front, Tessie's reputation was ruined. She later married Mr. Daly and Pa married Ma.