DS has chicken pox for the third time. He got the first time at 14 months but I had breastfed him until he was 1 and maybe because of this it was a pretty mild dose. Exactly 1 year later he picked it up again and had it pretty strong so when his sibling caught it 2 weeks ago (for the 2nd time), I wasn't concerned but it's another strong case! Should I consider getting him vaccinated as obviously his own immune system isn't developing immunity enough to protect from reinfection?