Duke Preston is Ray's father and Miles and Louie's grandfather. He is potrayed by Ernie Hudson, who starred in the film, Ghostbusters.
He is an old school no nonsense ghost, who doesn't like associating the same presence with humans. After his son Ray speaks up to him, he has a change of heart. He is hard on his son, but respects him when he finally stands up him, and dearly loves his grandchildren. He also doesn't like change. Much like Ray, he loves Jazz music.
- Just like Ray he's very good at playing the saxophone.
- He was the first ghost to haunt the Hathaway house.
- He's a level 12 ghost and is the scariest non-evil ghost.