Born in Saint-François of Madawaska, Delphine was one of the five daughters of Docithé Nadeau and Edith Sirois, who became nuns at the convent of Saint-Basile. Delphine had attended the boarding school of the Ursulines of Quebec, where she had studied painting. She taught for a while before entering the convent at Saint-Basile in 1888. She continued to teach, worked at the sacristy, attended to the priest and the sick.