|Title||Lord of Barrowton|
|Died||In 283 AC, the tower of joy|
|Spouse||Lady Barbrey Ryswell|
Lord Willam had been married to Barbrey Ryswell for less than half a year before the outbreak of Robert's Rebellion. Barbrey gave her husband a fine red stallion, the pride of the herds of her father, Lord Rickard Ryswell. Willam vowed he would return to her mounted on the steed. Willam was present at the wedding of his liege, Lord Eddard Stark, to Lady Catelyn Tully at Riverrun, and he made bawdy remarks during the bedding custom.
Willam was one of six companions who accompanied Eddard to the tower of joy in the Red Mountains of Dorne, where Lord Stark sought his sister, Lyanna Stark. They were opposed by three Kingsguard, however, and only Eddard and Lord Howland Reed survived the ensuing battle. Eddard buried the fallen in cairns raised from the tower's stones. Lord Stark returned the horse to Willam's widow, Barbrey, when he returned to the north.
A Game of Thrones
A Dance with Dragons
Barbrey Dustin, the widow of Willam and the Lady of Barrowton, reveals to Theon Greyjoy she still resents that Eddard brought Willam's red stallion back from Dorne but not his bones. If Eddard's bones are discovered, she will prevent them from being laid to rest in the crypt of Winterfell.
Quotes about Willam
—thoughts of Catelyn Stark
Ned Stark returned the horse to me on his way back home to Winterfell. He told me that my lord had died an honorable death, that his body had been laid to rest beneath the red mountains of Dorne. He brought his sister's bones back north, though, and there she rests ... but I promise you, Lord Eddard's bones will never rest beside hers. I mean to feed them to my dogs.