Born about 1920, Mary was the eldest of the four children of William O'Hara of Moigh, Cootehall, Co. Roscommon and May Fitzgerald fom Co. Limerick. She entered the convent (possibly Dominican) and became known as Sr. Venancius. She lived in the Sutton area of Co. Dublin.

Sr. Venancius was a niece of Nora McCormick and Louis O'Hara (see previous photos).