My BIL's one-year-old DS had chickenpox last week. Therefore there is a good chance that their six-year-old DS will come down with it at some point soon, and as it is infectious for two days before the spots appear, there is obviously no way of knowing when they will be infectious.
My MIL is having a family gathering on Easter Sunday. Now, the thing is, neither I nor our 10-month-old DD has had chickenpox before. Too risky to go? I'm sure somehow we will be made to look the bad guys if we don't... But I don't want to unneccessarily expose myself or baby to what can be a horrible illness!