Born in Dublin in 1956 and brought up in Goatstown, Marita went to school at the Convent of the Sacred Heart, Mount Anville, later working in the family business, the bank, and a travel agency. She has four children with her husband James, and they live in the Stillorgan area of Dublin.

Marita was always fascinated by the Famine period in Irish history and read everything available on the subject. When she heard a radio report of an unmarked children's grave from the Famine period being found under a hawthorn tree, she decided to write her first book, Under the Hawthorn Tree.