Frank's wife, who becomes Narnia's first queen, is Helen. She joins her husband in the newly created land and is crowned Queen Helen by Aslan in The Magician's Nephew.
Helen begins the story as an ordinary woman living in London with Frank, a cabby. After Digory and Polly reach Narnia and witness its creation, Aslan brings Helen into the new world so that Frank will not rule alone. Her arrival also reinforces the story's connection between familiar modern England and Narnia's earliest history.
Frank and Helen remain in Narnia as its first royal couple. Helen is described as the ancestress of the Archenlanders, and their descendants help establish the human dynasties that later shape Narnian history. Her role is brief in the novel, but it has long-term importance for the series' fictional genealogy.
Polly is Helen's commonest mix-up because Polly is Digory's friend and one of the children who witnesses Narnia's creation. Mabel is Digory's mother, while Susan is a later Pevensie queen; none of them is Frank's wife.