My infant has not been sick, but she's only five months old and ebf. My 3 yr old was ill when he was five months old, for two days with a slight runny nose, then he wasn't ill again until after his first birthday. The other three were ill for the first time between their first and second birthdays and since then, the four oldest have averaged being ill twice per year. Their illnesses have been very mild and resolve within three days at worst. They have extreme immune systems, so their fevers run high, if they vomit, it all comes out in one or two episodes that are total clean-outs, and then they recover quickly. They have never continued to vomit after being given fermented broccoli brine to drink following vomiting.
The two oldest have had mumps, measles and all but the infant have had pertussis. None were ill longer than 3 days, though the pertussis had them coughing three or four times every evening for a few weeks, but they were absolutely normal in energy and otherwise the rest of the time. I mean that they actually only coughed three or four times each night.
I used to try to stop illnesses with silver water, tea tree oil, and vitamin C, which was effective, but when we moved up here, I read about strengthening the body through illness, and have since made that our goal when ill. So, I reserve silver water for cleaning wounds, and treat illness with drink and/or food (depending what it is), cod liver oil, and rest. I also assist fevers by making sure the child is well-covered/insulated with blankets, but not to discomfort. My dc prefer want to be hot when their bodies are hot; they never ask to be cooled down- ever. This assistance to the immune system, rather than attack of the illness, has been very effective. We also quit grain and dairy and have been detoxing from that, which has been interesting.
We live on a farm, don't spend much time with other children anymore, but when we did, even when a sick child drooled into my child's mouth (yuck! It was unintentional), he didn't have any symptoms, nor did any of his brothers later on. We were confident that our children would be fine when around other people's sick children, because they were. One friend's home used to cause us all to be sick for days afterward, though. It happens (and this may only be correlation), that they use a LOT of cleaners and even bleach their toys. We use water around the house and Dr. Bronner's for dishes. I figure that the human body evolved and adapted alongside all the little buggly things that people now try to kill because we discovered their existence, so if we don' disturb the natural balance, we should get on just fine together. So far, so good. Our eldest is 7 1/2 yrs old and none of our children have had any serious infections.
Our six yr old had a wart that was concerning and perplexing me, but we quit grain, and two days later, it had almost completely resolved on its own.
On the issue of immune systems, it is true that a weak immune system can seem strong because a person never seems to show any direct symptoms of illness, but sometimes a person can be riddled with illness and have such a weak immune system that it doesn't function. I was thrilled when after years of being unwell, but never sick, I coughed out phlegm. I felt like the bottom of my lungs were heavy with fluid for years, but I never coughed or had any immune response at all, but I was constantly very tired. I know most people wouldn't rejoice in coughing up phlegm, but for me, it was the first sign that my immune system and body were healing!
I have a friend who swears her daughter never gets sick, but this child is always, ALWAYS unwell: she has pale, pale skin with dull hair and is generally tired, not alert or curious, slurs her words at 5 years of age, etc... Her brother has never not had a runny nose, since he was an infant, and he is now 3 yrs old. The dd was vaxed initially, but isn't anymore, and the ds was not vaxed. They pay little attention to the health of their food, though, so they aren't healthy. Pudding cups because children need carbs to feed their brains, is as far as they understand nutrition, or care to learn, so their dc are always unwell, but never sick.
ETA: None of my dc have had ear infections. I had them along with strep throat at least twice/year for years when I was a child. I was also given lots of abx.
Edited by PreggieUBA2C - 12/30/10 at 6:34pm
What I do believe is that they would be even more sickly if we did not BF, did vaxs, etc... while they might be ill often, it isn't severe in DD1 and DS, it is in DD2 due to her lung issues resulting from pertussis as a newborn. 
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