I'm sure you will get a ton of advice. . . . and I could go on and on about my son. But, here are a few things:
Get peanut butter out of the house and get Sunbutter. Your boys won't even notice. We buy the 5 lb. buckets on-line for a great price (I supply my son's preschool with Sunbutter for everyone). You can even bake with it, but you have to tweak leavening, or the green in sunflower seeds will come out (tastes fine, just looks strange sometimes.)
This is a bit controversial, but some folks gave me this advice and I followed it, and while there's no way of knowing whether it worked or not, my son's severe reaction to pollution is gone, his asthma is gone and his allergies to dairy and egg are gone. . . . two things we did, that are healthy anyhow:
We beefed up his exposure to good fats in Omega 3-6-9s. There is evidence that it helps a kid's immune system "calm down". We did a simple supplement with our son, Nordic Naturals omega supplement. It came in a capsule and we just squeezed it out into juice. Don't buy fish oil at Walmart, the quality is nowhere near what you'd want. We also put ground Flax seed in alot of stuff.
The other thing we did was put him on a great children's supplement called Usana. Again, some research shows that it helps those little allergic bodies settle down and give up their fight against normal things like food, etc. Check out Usana on the net, the kid's vitamins are Usanimals.
And, if it turns out those things didn't work, well, then you've got your kid on a great supplement of good fats and vitamins, which is especially needed when there are alot of things your kid can't eat.
We did this for 2 years and when my son was 3 and we took him to the allergist for more testing, I started to cry when they said "all that he's allergic to is peanut and cat!". Again, I know there is no way to know if this worked, but we're believers!