I don't know if this will help you make a decision or not but here is a story for you: My boss gave her baby Chicken Pox through accidental contact with her shingles. The baby had chicken pox for a short period and is just fine. My boss didn't want to take her out in public with all the little spots on her, but otherwise it was uneventful.
So, on the one hand, my boss does not have to have her vaccinated now that she has natural immunity, but on the other hand, it was an "average" case of CP. I think with any illness there are varying degrees of severity, so one never knows. Her baby was about the same age as yours at the time, maybe a little younger. Good luck with whatever you decide.