Take him off of wheat (anything with flour in it) and dairy!!It won't hurt him a bit to take him off those and see if things get better. It can only help since both of these foods encourage your body to line cells w/ mucus, which doesn't help the body when it's already having a hard time breathing! The doctors won't always tell you about the effects of severe food allergies, there's some things you just have to figure out for yourself. Whenever my little brother (who had a wheat and dairy allergy) would eat too much of anything with flour in it, he would develop the exact same symptoms that you just described.Don't worry- there's lots of flour alternatives and it will be very easy to adjust a 2 year old to the taste of spelt flour and rice milk. Health food stores are abundant in all kinds of alternatives to wheat (most of us actually lack the enzyme to process American wheat, but have lived with the side effects for so long that we don't recognize them anymore, but health food stores cater to the people who do recognize their wheat intolerance). Once you get the hang of what he can/ can't eat, you won't need the health food store- it will be 2nd nature. I can elaborate on why wheat causes problems in some people if you'd like, but it's basically because allergy (simply lack of a certain enzyme in their body that other people have) = inflammation. Inflammation in body = mucus (to protect the inflamed cells). Too much mucus = clogged airways and body producing fever to fight the perceived infection. Find a doctor who will get to the ROOT of the problem (generally an alternative medicine doctor, but there's some med doctors out there who are learning to take care of the root). Don't put up with people telling you they're not quite sure what's going on, here's some antibiotics for the symptoms. Antibiotics can cause a host of other problems now and later on in his life. If he has RSV, by all means, use the antibiotics. But have someone clearly make a diagnosis before trying to treat the symptoms- treat the root. Good luck!