Autism isn't something a person has, or a shell that a person is trapped inside. There's no normal child hidden behind the autism. Autism is a way of being. It is pervasive; it colors every experience, every sensation, perception, thought, emotion and encounter - every aspect of existence. It is not possible to separate the autism from the person – and if it were possible, the person you'd have left would not be the same person you started with.
One of the admirable features of British novelists is that they have no scruple about setting their stories in foreign settings with wholly foreign personnel.