Autism is a very real condition. This is very sad to read and you and your fellow passengers should walk a mile in the shoes of people such as
@steve50's before you are so quick to judge. I'd like you all to sit on an eight hour flight with an autistic person and see how you got on.
This sort of thing makes me really angry. There is no way for you to know whether or not a child, any child has ASC, or not. People that deny autism are just ignorant, old fashioned, out-of-touch and they make the lives of autistic people and their parents or guardians all the more difficult with such attitudes. Autism has been around for a long time and people like you need to accept that it is a very real disability that wrecks homes and lives.
It's very sad that people still think this way.
Autism has been around since the forties.