i know i had chicken pox when i was little and i was just covered from head to toe i itched like crazy and i could not wear any clothes my dad said he felt so bad for me because i was just laying there grinding my teeth because of all of the itching.  He kept calling the dr asking for something to ease it for me.  All 3 of my children had the vaccine, my oldest may have had them and may not we will never know there were maybe 5 on her entire body and even if she had 25 i would say it is worth it for her to get the shot and not have to go thru what i did.  so far the other 2 have not had any signs of it.