I'm sure your friend is a very nice person and she seems like she means well. But seriously why would you go through all that trouble to have your kids get sick when they are younger. Both my kids are up to date on their vaccines. My son has been hospitalized twice in his short 2 1/2 year life here on earth. First time was for a staph infection. The second time was for severe dehydration from rotavirus. Neither one of which I could control nor did I know much about. Parents not vaccinating their kids gets me very angry, because why would you put others at risk for an outbreak of something because of your selfishness towards your kids. Parents like this seem to forget the big picture that we are all here on this earth together, we can not walk around and put ourselves or our children in a bubble. To me it's a simple comparison; if you've had a heart attack and the dr. puts you on medication to help prevent from happening again, and you know there are definite side affects, are you going to risk another heart attack because of side affects. Tons and tons of kids get vaccinated and don't have any problems with the vaccines. I just think this is a very selfish move and to send a sucker through the mail to have one kid suck on then send it back, well I'm not an expert by any means but hello contamination of something that someone else might be sending through the mail, thus how an outbreak starts. That idea just sounds absolutely insane to me.
Again I'm not trying to down your friend at all or hurt yours or her feelings. I personally would stand up to her and tell her what your thoughts are. If she is your friend then she will value what you have to say.
I hope I didn't offend anyone by this, I just get so frustrated when it comes to children and their well being.