- Brother of actor Sean Astin, who worked with Dominic Monaghan on the Lord of the Rings films as a fellow hobbit.
- Son of Patty Duke and John Astin, famous for playing Gomez Addams in the 60's version of The Addams Family, Professor Gangrene in the Killer Tomatoes movies.
- Dropped out of Johns Hopkins University, where he was majoring in history.
- Brother-in-law of producer Christine Astin.
- Uncle of actress Alexandra Astin and Elizabeth Louise Astin.
- Dominic Monaghan was his roommate for a while.
- Nephew of Ray Duke.
- Has three other half brothers: David, Allen and Tom.
- Played Andy on The Facts Of Life.