[munksbeer]

> When I was around 6, I resolved not to become one of those rubbish adults who doesn't know anything but thinks they do: since then, I've been paying attention.

I'm not sure I understand. Are you autistic yourself?

In any case, thank you for your lengthy and informative replies. We live in the UK, so our path will be different from the US. As the parents, our strong instinct is that he is not "just a typical four year old". We have known something was atypical since his first year. I am so tired of external people telling me how he is "just being a child". We have another child. We know what "just being a child" is. And I'm tired of being told to dismiss our instincts.

We know that a diagnosis won't solve anything, and that we can and are learning as much as we can to understand the way he perceives the world and what works for him and what doesn't.

Thanks again for your replies.