My grandson is now 6 and in a special education class. He was also evaluated and is being treated thru the school district because of a speech delay. The district has not asked to do an autism evaluation. They've said that it does not benefit the child to place a label on him this early. They do use curriculum developed for autism as well as the specific delays with which each child has been diagnosed.
I've done quite a bit of research and believe that my grandson is somewhere on the autistic spectrum. I've become comfortable with that idea as I see him develop. He has many strengths as well as handicaps.
A couple of weeks ago I saw a film about a Son Rise program in which they suggest that children can be taught to engage with the world in a "normal" way. The speaker had been diagnosed as autistic as a preschooler. I know that the idea of a "cure" is not generally accepted and I'm not looking for a cure. I did find the film encouraging in that many of the techniques that they use at their center are similar to ones that we are using with my grandson.
I also saw a couple of reality programs on TV that were not about autism that showed men who were autistic and who led normal lives with wives and children. Their personalities seemed to be more intellectual than emotional. I've known lots of people who seemed similar to the ones on TV with an autistic diagnosis. All of them, the ones on TV and the ones I've known, had successful lives with families or had chosen to remain single and still seemed happy.
My general philosophy of life is that everything happens for a reason and for me that reason is to help me grow and become more mature in a healthy way. I believe that my grandson is and will be the person that he is intended to be. It is my role to help him as much as I'm able. Others will also help him in ways that they are able.
I also believe that all of us have choices about who we become. It is not true that we can be whoever we want to be. We are limited by our genetics, environment, and experiences. When we recognize our limitations as well as our strengths we can focus our effort toward becoming a successful and happy person.
I've seen my grandson grow from a defiant, angry preschooler to an energetic and still difficult to manage first grader. He was in a therapeutic preschool because of his anger and acting out and he's now doing well in a regular special ed class. He doesn't seem to need friends tho he is friendly. He has an active imaginary life with imaginary friends with whom he doesn't have to speak clearly. He does work on having better speech and is patient with us who don't understand what he's saying some of the time. He gets a break from the difficulty of working on being like other kids by having his imaginary friends. I worried about this at first but no one else seemed to be concerned and I came to see this as beneficial for him.
I would discuss with the school officials why want to do an official assessment. I would ask how having a diagnosis would change the way that they are treating him; how it would not only help them but how it would help your son and you. If you do not think that an assessment would be beneficial I would not give them authorization.
I empathize with your loss of your baby. This certainly does add stress to your life. In your situation I would ask how I could best manage my life with my son in the situation in which I'm living. For me knowing that my son is most likely autistic and how I can help him would reduce my stress. But if knowing does not provide a better focus and help me to feel more confident in how I could help, I'd not seek an answer. I spent months wanting to know. My daughter doesn't think it's important to have a diagnosis. She wants to deal with specific behaviors as they appear. I've come to agree with her view.
I was only able to relax and accept not knowing after I accepted that autism was a strong possibility. Until then I was anxious.
Consider the possibility that not knowing increases your stress because you don't want to believe that your son is autistic. Perhaps your stress will decrease if you were able to accept the possibility. You do not need a test to do this. The school district may need a test to provide better services.
Apparently our school district has a different philosophy and perhaps focus. They're able and choose to work without an official evaluation. Perhaps your district can't do that.
Focus on finding our information and use that information to make a decision. Perhaps working with a counselor or therapist would help you to deal with the grief that a child's death creates and then the grief that having an autistic child creates. You are already grieving the possibility of autism. Allow yourself to grieve in whatever way works for you.
Also keep in mind that Joshy is also grieving his sister's death. That will influence his behavior. I recommend grief counseling for all of you.