If you see a child with autistic-like behaviors at age two and three, the worst thing you can do is just let them sit and watch TV all day. That's just the worst thing you can do. You need to have a teacher working with that child, working on teaching language, working on social interaction, working on getting them interested in different things, and keeping their brain connected to the world.
My mother was always expanding my art skills and getting me to paint different things. You always got to push some. And, I mean, I learned basic things like getting up on time, how to shop - you know, you don't touch things in a store you're not going to buy. These things were taught very young. I don't see today enough of this basic, you know, basic skill teaching.
If you have a 2-year-old who is non-verbal, don't wait until you get a diagnosis at 4. The child needs one-on-one teaching with an effective teacher now. This can be a grandmother or a teacher or someone from the community. Grandmothers are especially great. There are a lot of grannies around. Go to your church for help.
The thing is, autism is a big spectrum. Going from folks who remain nonverbal, all the way up to, ya know, famous scientists and musicians. And we've got to work on strengths. We also have to work on teaching basic manners and skills.