Who is Uncle Dock from The Wanderer and what is their importance?

Uncle Dock is Sophie's favorite uncle. He is a carpenter in real life, and he is in charge of all maintenance and repairs aboard The Wanderer. Dock is described as easygoing and calm, a direct opposite of his two brothers. While the rest of Sophie's uncles didn't want her aboard The Wanderer, Uncle Dock fought to include her, despite the fact that she's a girl.