Hi Amy,
Welcome to the board, you definitely found the right place and I'm sure you will get a lot of advice from parents who have experience. My DD turns 4 next month and though she has sensory issues they were never to the level of needing therapy. We just took things slow with her. As a baby she would out and out refuse to walk in the grass because the sensation of grass on her feet freaked her out. That and leaves, but we baby stepped it with her and she slowly came around. That and having two big dogs she absolutely adores helped get her past the fear of grass. We also had some issues with light and sound but she has seemed to gotten over most of that. We would keep sunglasses in the car for her because the sunlight was too intense for her and would leave her in tears. Even with a sunshade on the window it wasn't enough, but this year she hasn't needed the sunglasses or the sunshade and has adapted to the bright light. The other issues we had was food. She was basically a vegetarian because she couldn't stand the texture of meat even as baby food. So we set up rules that she had to at least try everything on her plate. Most of the time it was met with faces and she would refuse to eat it beyond one bite, but enough times of the same item showing up on her plate she adjusted and added it into her likes.
My DD has a classmate very similar to your son and he is in therapy. His mom said it is a slow process but they have seen improvements. She also has informed me on many occasion about my DD and her interaction with her son. DD is very protective of him and when someone in class shouts or gives him too much attention, DD quickly shuts it down. His mother adores DD because she just seems to understand. DD has such a high empathy and doesn't like to see others suffer. Even at his birthday party when he became very upset and had a complete meltdown about his dinosaur pinata getting hit and his mother couldn't calm him down; DD stepped in and rubbed his back and talked to him for a little while. It was such a sweet moment and very touching to see how her little act helped him in a way nothing else did. He accepted the fate of his dinosaur and was able to continue on with his party.
