Mary Ignatia Gavin, C.S.A., (January 1, 1889 – April 1, 1966) was an Irish-born American Religious Sister, better known as Sister Ignatia, belonging to the Sisters of Charity of St.
Augustine, who served as a nurse.
In the course of her work she became involved in the care of those suffering from alcoholism, working with Dr.
Bob Smith, a co-founder of what became Alcoholics Anonymous.
In this work she became known as the alcoholic's "Angel of Hope".