I was discussing this with a few other parents of children with autism: When did you tell your child they had autism? The answers surprised me, so I thought I would share them.
I told my children when they were very little, right after they were diagnosed. 2 and a half for Alex and 21 months for Nathan. So they probably don't remember a time when they didn't know they had autism. We've used the diagnosis in any number of explanations: why they get frustrated learning new things, why it feels frightening to try something new, why they get upset during transitions.
We've had a couple of challenges with our system. Nathan is starting to get to the point where he challenges us that he shouldn't have to do something because of his diagnosis. (Which lets us trot out the parental lesson: just because something is difficult doesn't mean it's not worth trying.) He also asks why the standards for Alex are different than for him if they both have autism, which led to us trying to explain the concept of a spectrum. And Nathan also worries that he's going to get worse, which we've tried to reassure him won't happen.
Another family recently told their eleven year old that he had autism. The child was undergoing testing and became suspicious about it. He wouldn't accept their excuses until they told him the truth. He was very shocked and upset that they hadn't told him. His mother told me that she thinks he'll be relieved once he has time to process it. She chose not to tell him because she didn't want him to feel labeled or restricted. It's only recently that he became aware of a gap between him and his peers and so she was planning to tell him soon and had asked for professional help on how best to explain it.
A third family has an adult with autism (25 years old) and doesn't want him to ever be informed of his diagnosis. They have managed things from behind the scenes for years but don't want him to feel restricted or different from his peers. They continue to have him undergo intensive therapy to deal with his behaviours and challenges in the hopes that he will become effectively normal and not have to be told.
My husband found out he had Aspergers in his forties and once he got past the initial denial and shock, he was relieved. It explained why he thought differently from other people and why things which were simple and intuitive to them remained complete mysteries to him. He said he doesn't know how he would have felt if his parents had known and chosen not to tell him. He remembers being horribly depressed as a teenager and young adult because he knew something was wrong but he couldn't understand what.
Would I have told Nathan he had autism if we hadn't had Alex? I don't know. There was no hiding Alex's autism. It's quite severe and is something we deal with constantly. When Nathan was diagnosed, I had no idea how severe he might be and so I was honest with him. I told him the therapists were coming to play with him to help his brain to grow and learn because he had a special brain and needed special teachers. I had no idea how much he understood. If I had known he was going to be relatively mild, would I have told him? I might have decided not to, so that he wouldn't feel isolated. But I'm glad it's not something I have to have a Talk with him about.