When i first added my sim self's parent's to my save, i got a notification that his father had died on another lot. It was too late for him to save his father, his ghost had already been culled. So when i went to his parents apartment, i added my sim self's elderly mother to his household and she was about to go next! She passed later in the early hours that night.
He sent her ghost to the netherworld but since then i re-created his parents again from scratch using old screenshots and the are now back in the game.
