The Eight is Enough pilot was filmed in the spring of 1976. ABC didn’t pick it up for a fall premiere, but retained options on the cast through the rest of the year. Mark Hamill went off to film Star Wars in the summer of 1976. That fall, ABC picked up Eight is Enough for 9 episodes for a March, 1977 premiere. Hamill asked to get out of his contract and the request was declined. A week before filming was supposed to start on episode 2, Hamill had his car accident, and was released from the show.
Mark Hamill played the oldest son in the piolot episode, prior to Grant Goodeve. Then when the series was picked up by abc, he was unavailable. He was working on some science fiction movie.
NO, he got in that car accident that almost killed him and disfigured him for life. Remember? He never looked exactly the same after that...he had to have a lot of reconstructive surgery. But I'd never seen this...very interesting.
This show had the same problem as the Waltons. It's like the casting director purposely picked the ugliest gooniest weird-looking kids they could find. Who the hell knows why.