Responses
I'm not positive but I think in one of the beginning chapters it said that when their clan gives birth to a child that isn't Aehri then that person will be forgotten.
Ohh, I'll investigate that
So... the spirit made Estrella's brother forget that he saw him, and an Aehri dies if they're forgotten....
At first I thought that when Aehri die, they are forgotten, which would mean that Estrella's mother died of natural means and that's what caused everyone to forget about her. But, instead, she died BECAUSE she was forgotten, aka everyone forgot about her and then she died. There is noooo way everyone forgot about her naturally, so someone or something made them forget. It might be spirit, or it might be something else, but for now I find him very suspicious...