Ach. Yeah, the oral defensiveness can be a bear to deal with. For a start, you might try getting him some of the mouth exercise toys. Include him on picking them out; he will have valuable input on what looks fun and what doesn't. I have oral defensiveness, and when it's bad, there's a LOT I can't eat. It tends to get worse when I'm under stress, too, so that's something to consider. For me, it's textures. I have trouble swallowing things when the texture is "wrong," for whatever reason. Meat is a big culprit for me, because it begins to feel "dry" after you chew it for a while. Also oatmeal, grits, and eggs. The texture of those have made them almost impossible for me to eat for years, even when I like the flavor. Getting more mouth input from oral toys can be a help for this. It gives him the input he needs to "organize" how he feels, and it helps him relax and deal with the changes in texture and such better. It's a tough nut to crack, though, so it goes without saying that the nutrition value of food is going to be very important for a while. The big thing, though, is to know that it does fluctuate, so it probably won't be the same all the time, and it can get better with some therapy. And if you lower some of the stressors in his life, that can also be helpful.

One nice thing about treating SPD is that when you help one sense, often there is some improvement in others, as well. So when you have several things you treat at once, you can often get a cumulative effect that spills over into senses that are harder to treat. So I'm sure that weighted blanket you got him is helping, and if he's after his brother's therapy ball with a vengeance, well, it can't hurt.

Sounds like things are a bit difficult right now. Hope they start doing a bit better soon for you!