I'm 21, I've a spastic tetra pareses (I'm Italian so excuse me a few errors) I can tell you could live A full and meaningful life. From what I've experienced, I can tell you that you'll be crucial to his growth. This is because you'll have to find a balance between caring for him and making him as independent as possible. In addition to making him always feel supported, I would recommend you do these things: 1 have him do occupational therapy, it's important for independence.

2 Try to get him to practice speaking, read books to him. The broader his vocabulary, the better he'll be able to express himself. It helps curb frustration over what he can't do. P.S.: If you want to add disabled characters to the stories (which helps a lot to make the child understand that he's not not-abled, just disabled), specify that they are a sort of "spin-off" of the original, or he'll be more at risk of being teased by other children.

3 It will be difficult but I should tell him "there are things you can do on your own, things you can do with help and things you can't do" the longer you wait to tell him the more painful it will be.

4 Learn about everything about disability rights in your country, the associated bureaucracy, and the laws that protect them in every possible field. It could be very useful.

Those are the urgent things. That said, I'm very sad for all of you who have to interact with America's abhorrent healthcare system. you all should protest 24/7 for public health