First of all, don't add soy or feed him soy as it is high in estrogen. Read more at www.mercola.com
If he is having ear infections, he will probably continue having them when the antibiotics have been taken away for awhile. Rounds of antibiotics are not at all good for anyone.
I got rid of my problems with Peaceful Mountain Sinus Rescue which is a silver product. Mine were sinus issuses, but swabbing the ear with silver or with hydrogen peroxide (much cheaper)kills germs and bacteria.
He may also be allergic to milk if you think there is a link between that and his problems. I do food allergy testing as do many other practitioners. You might consider that, as well.
He may also do better with goat's milk as it is easier to digest. And chiropractors often say they can get rid of constant ear infections. So there are a few other things to try. You don't want him getting immune to the antibiotics from using them again and again as he grows. One day he may actually need one.
L. Mac Dougall, Holistic Health Practitioner