You know, I'm one of the first to say, when my son eats something off the floor or sticks his hand in his mouth that it's all about immunity building. That said, I would *never* knowingly expose another person or child to an illness -- especially one that involved a fever, antibiotics or worse, hospitalization. If he had a really bad cold, I'd keep him away from others or at least give others a heads up. It's just common sense. Our pre-k and MOMS Club has a policy -- no coming in if you had a fever less than 24 hours ago, on antibiotics less than 24 hours, etc. It's just common sense. For one, the sick child needs some rest and secondly, why expose others?? Also, we have a kiddo in our playgroup who is on chemo for an autoimmune issue and she has a compromised immune system -- obviously. I've never had chicken pox and despite the vaccine, still don't have complete immunity. I think your friend's attitude was cavier, callous and even selfish. I totally understand wanting to get out of the house, but if your child is legitimately ill with something you need to either a) let the host/ess know or b) stay home.