Mary Power (“Mam”) is Vivian/Niamh’s biological mother. Born in Ireland at the turn of the twentieth century, she immigrates to New York with her husband Patrick and her three children, Niamh, Dominick, and James. She becomes pregnant with her daughter Maisie during the voyage to America. Mary is frequently depressed, which can make her neglectful of her children. Still, she values education and teaches Niamh to read. In Ireland, Mary’s fights with Niamh’s Gram are part of the series of events that lead to their family’s departure from Ireland. After Mary’s husband and sons die in a house fire, Mary is institutionalized in a mental hospital.