Is named for Viet Cong resistance leader Nguyen Van Troi and Irish revolutionary Jeremiah O'Donovan Rossa. Garity is his paternal grandmother's maiden name. Changed his name to Troy when he started acting.
Had an unbilled role in his mother (Jane Fonda) and grandfather's (Henry Fonda) 1981 film On Golden Pond.
As a teen, ran away with the circus when he became infatuated with one of the performers.