According to the rules of the earth Dragon Balls, a person can only be brought back to life once. Do the people that Majin Buu and Cell (or any other two villains) both killed remain dead despite the wishes used to bring them back? Or do these rules only apply to main characters?
It's been a long time since I watched the Majin Buu saga, but I do recall that Buu killed many people and destroyed the planet. I'm asking this question because I don't recall Goku and friends ever expressing any concern that some people wouldn't be able to be revived because they were killed twice (again, haven't seen it in a long time, so I can't be sure).