The youngest child of actor Cyril Cusack and his Australian wife she was brought up and educated in London. She started acting at 17, her first role being in the television series of Dr Who. She then quit a university course in drama to play Constance in BBC'2's Sophia and Constance. Her next big role came with playing Nanny Carmei in Coronation Street and a stage role in Sir Peter Hall's Company at The Old Vic in Prayers of Sherkin and Chekov's Three Sisters with her father and her three sisters, Niamh, Sorcha and Sinead