Unser Jr. and Sr. are a father-son duo of race car drivers. Al Unser Sr. is a four-time Indianapolis 500 winner, while Al Unser Jr. is a two-time Indy 500 winner. Both have also won numerous other races throughout their careers. The Unsers are the only father-son duo to have both won the Indy 500. Al Sr. was inducted into the Motorsports Hall of Fame of America in 1990, while Al Jr. was inducted in 2006.