Soy is just as bad if not worse than dairy. If you are having problems with these foods already then try www.neocate.com as it is for babies that cannot have either soy or dairy. I would keep them away from any wheat and eggs products as well which also means no vaccines as these ingredients are in vaccines as well. You don't say how old they are but it sounds like their immune systems are in needing some assistance. You could also look into probiotics and omega3.