Non playable sim

I have a sim that’s just hanging around, he shows in the family portrait but when I click to make sim playable, I can choose him but no option to make him playable, I also cannot remove him. I really want this sim gone as he is like 4 generations old.  Is this a unfixable bug? I’ve tried uninstalling and reinstalling the game, I’ve tried moving him to a different home, nothing works.