Born: Established: Cootamundra, Cootamundra - Young - Harden area, Southeastern NSW, New South Wales, ; Died: Ceased: 1983 Melbourne, Victoria,
Mary MacMahon was educated at Loreto convents in both Normanhurst, New South Wales and Ballarat, Victoria. In January 1923, she married Dr John Joseph Daly, a nephew of the founder of St Vincent's Hospital, Mother Berchmans Daly, and served on the St Vincent's Hospital auxiliary as honorary secretary and later acting president.
Daly was president of the Catholic Welfare Association from 1941, a member of the National Council of the Australian Red Cross Society, and executive member of the Council of the Victorian Division. Her services to social welfare were acknowledged with her appointment as an Officer of the Order of the British Empire in 1937, Commander of the Order of the British Empire in 1949, and Dames Commander of the Order of the British Empire on 7 June 1951. The Catholic church awarded her the Cross Pro Ecclesia et Pontifice in 1951. She was also awarded a long service medal from the Red Cross Society in 1940 and honorary life membership in 1971.Apart from children's fiction, Mary Daly also wrote Catholic Welfare Organisation: Its Work for the Men and Women of the Services during World War II, September, 1939 - June, 1948 (1948).