Mary is an American nomadic vampire. She appeared in Breaking Dawn to help as witness against the Volturi in their confrontation against the Cullens.

When the vampire Alistair left out of fear of the Volturi, Mary declared her intent to remain with the Cullens. She befriends Randall on her way to Forks, though they don't travel together. After the Volturi retreated peacefully, she went on her way