I am looking for suggestions for a product I can use daily to boost my LOs immune systems. DS1 is 3 and DS2 is 19 mo. They were sick on and off all winter and have been sick a couple of times this spring as well. I am very serious about doing something preventative. I have gotten some suggestions from friends including biocidin, olive leaf complex and goat colostrum. Can anyone provide more information about these choices or suggest something else? I also saw the Dr. Sears immune boosting chews, but I haven't heard anything about their effectiveness.