Hi Amber, When the chicken pox vaccine came out my daughter was 2 and I had her get it. About 4 months ago (She is 5) she got the chicken pox because it was going around at school, in fact 8 children who had the vaccination got them. In all cases they only got around 6 pox which is considered mild. When I called the endo. they said to watch carefully for fever, if she got fever she was to be admitted to the hospital. She did not get fever. Also they put her on a drug for Adults (I wish I could remember the name) It's used for high risk patients who get chicken pox and also for shingles and herpes. She came through it like a trooper she didn't even itch that much. She did miss a week of school tho. So my conclusion would be that if she did not have the shot things may have been much worse. Good luck, Linda