it's more of a reason though
Surprisingly, this was never used to justify his actions. The abused was quickly address here. Grayson's mental condition is the one that makes his actions complicated because he never intent to cause harm people but it was always the result of his help. Ashley never tolerates him. He was supervised than his other siblings who share the same phenotype like him. While the other story brought up sad back story for the main characters, for Grayson it was just an explanation for his condition.
It was never about childhood or abuse lol.
his childhood is not an excuse.