I am curious if the autistic behaviors I am seeing at this age of 3.5 are indicitive of future behaviors...did your child's symptoms progress over time? For instance, just because my son appears to suffer mild OCD and stimming right now, can/will these behaviors develop and worsen as he gets older? It it common for them to escalate as he gets older? Or peak at a certain age? Hopefully diminish? Please let me know your experience.
What a great question. Our kids do change just like regular kids. Some kids have great outcomes but I suspect the best outcomes are with kids that have had effective interventions and treatments. Yet some of our kids continue to struggle even with good treatment. So there's no crystal ball. I think as a parent you need to try to figure out how to get your child the best interventions, do all you can do within the limits of your circumstances, and know that you did the best you could. If I had to do it over again, I would have started with RDI sooner which is a great way for parents to learn how to connect with their kids.
My son who is 14 now only stims at home. He knows this is not good in public and will only pace in public which is much more acceptable. The one thing I did do when my son was young was whenever he chose to do the same thing over and over again, I refused to let him. The best advise I ever got was to challenge him in this regard. He wanted to touch walls at school the same way every day or go through the same door the same way, etc. I refused to let him. I constantly changed it up on him even when he would melt down. This is really hard but it totally worked for him. Now he does not have any OCD behaviors. God bless you!
About 10-20% of kids who get intensive early treatment will improve to the point where they no longer present as obviously autistic. There is a lot of controversy over whether they are fully "recovered" but they have overcome their major symptoms.
My son's behaviors come and go in waves as well. Unfortunately, as they get bigger and are on meds such as mine is, he outgrows his dose and then it takes some time to adjust. My son has some SERIOUS OCD issues and its really a crap shoot to find out what meds work with which meds. Some days he is great and you can carry on a perfect conversation with him, other days his conversations don't make much sense to us. He has increasingly become more aggressive as he gets older too (he is now 12 and was diagnosed with ASD when he was 2 1/2.) We needed to add an additional med to help control his impulsiveness and reduce his agitation/anxiety. We know that he will never "recover" and that is fine with us as long as he is happy and does to the best of his abilities. Some parents, I feel, put unrealistic expectations on their children only to be let down when things don't happen. I did grieve for my "normal" child years ago, but that didn't help to prepare him for what he CAN do today.
Just get as many effective interventions that you can while they're young and their brains are malleable. My boys are teenagers now and have progressed so much. The oldest is in college and has many friends now. We worked on the spirituality of the boys early on too... taking them to church, praying together, teaching them the Word of God. God has changed my children for the better! Trust Him.