That's not very considerate of your sister! You'd think she'd no better having been through pregnancy herself! DS had this a while back while a friend of mine was pg and I freaked out and stayed away from her for weeks! I spoke to my dr about it later, bc DS is in creche and I was wondering how to manage the risk of this and 100 other childhood illnesses for me when we were planning #2. He didn't seem to bothered. I *think* it was only a problem if you caught it and apparently it's really uncommon in adults. So hopefully you'll be ok. MAybe tell your MW, just so she can look out for anything? GL