Fonzie (Henry Winkler) tells Richie (Ron Howard) that he hasn't seen his father since he was 3. But in the season 2 episode "A Star Is Bored," Fonzie says his father left when he was 12. And in the season 3 episode "Howard"s 45th Fiasco," Fonzie tells Howard (Tom Bosley) that his father left when he was 4.
This episode takes place during 1960.