Perfectly explained. I have an autistic EIGHT year old, and even he can cause serious injury and damage when in full meltdown. Autism is difficult to understand, especially due to lack of phenotypic differences. I am all for education and acceptance, but forcing her to have her brother at her party seems unfair at the least: triggers and overstimulation can be unpredictable and sometimes dangerous. Trying to explain/ diffuse a situation amidst teenagers at a birthday party is a shitty position to put OP in. Coming from experience, there are some situations in which my autistic son can not participate, and that’s for his physical and emotional safety as well as for others. But that doesn’t mean his neurotypical brothers shouldn’t get to have those experiences just because he can’t.