Last year I had a newborn and a nineteen month old with (not yet diagnosed) autism. She took no notice of her new baby brother at all, I mean he may as well have still been in my tummy at least he was useful there.
Now I may complain that their relationship is strained at best but back then it saves my sanity. As a single mum I never had to worry that she might try and pick him up, poke him or feed him crayons etc.
So there we go, this is my positivity shining through for a change.