Would make fun of an aspergers child?
Or a child with down syndrome?
Or a Schizophrenic?
Certain mental health problems and disabilities can affect grammar. I've met enough grammar Nazis who think aspergers disorder actually means that a person is retarded, when in actuality a person who aspergers is likely to be smarter than the person calling them retarded. It all depends on the person of course, and I am not assuming that all aspergers me people are geniuses. It's just slightly more common in aspergers people, who may record memory better than most people do.
Einstein was dyslexic but I am sure he tried his best to perfect his grammar so that he could bring his findings to the world.
Schizophrenia destroys the intellect and causes a person to lose their proper grammar whether they are aware of it or not. These problems can happen to anybody no matter what education they may have behind them. My uncle became Schizophrenic in adulthood during the period he was supposed to go to Oxford university, unfortunately he lost out and wandered the streets the rest of his life.