Wylla is one of the women who has been reported to be Jon Snow's mother.
In the BooksEdit
Wylla is the woman Eddard Stark told Robert Baratheon was the mother of his bastard Jon Snow back in the days of Robert's Rebellion. Robert brings it up on the way to King's Landing, when he an Eddard are riding together, in "Game of Thrones". Robert asks what that woman's name was, and Eddard says Wylla, but Eddard doesn't want to talk about her. Robert remarks that she must have been quite a woman to make Eddard forget his honor and marriage vows for even an hour. Later, Arya meets a squire for Beric Dondarrion named Edric Dayne, the Lord of Starfall. (ASOS page 597) He tells her about Wylla. He knows her because she was his wet nurse and he says she was Jon Snow's mother. Arya wonders when she will see Jon again to tell him.