Gastric Sillitoe, the captain of the Wonderful Fanny, is married to Mrs Sillitoe. As a family, they often transport goods down along the Quire. His boat is commandeered by Stratford and his mercenaries while transporting captive goblins to Quirm. He and his family are rescued by Samuel Vimes and Feeney Upshot.
He employs Ten Gallons in the engine room of the paddle boat.