I have a 15 year old daughter who grew up with a large H on her nose. In those days,,treatment was not so available,,so we truly belived it was OK, to let it go away itself...Obviously now,,we would know better,,but more on the subject of the question you asked,...
Corinne said everything exactly what I would say...the only addtional thing I always stressed to my daughter..Is the feeling,,that once she is ok with herself,,and I believ children will be, ok, when they hear over and over from their parents who they trust..how beautiful and wonderful they are......once they know and feel they are beautiful and they truly belive they are..when someoene says something "hurtful"..they need to know,,that has not changed anything about who they are.....the other peoples words,mean nothing..
example I used..... My daughter has dark brown hair..... FACT...clear as day!!!..now if another child came up to her and said....EWWWWW you have ugly red hair....(no offense to red-heads,,just an example)..Would that be a true statement?? Should she feel hurt?? Was it accurate.... Is her hair even red.......
Get my point....Only from within can a child really protect themselves from hurt...As parents we need to instill in them,,how truly beautufl they are!
Now of course,,,that doesn't mean that they won't be picked on,,but, they can acknowledge their b-mark, and educate, and explain. to others what it is...It always gave my daughter a sense of POWER... She had knowledge about something that most people didn't.
Anyway,,, I hope this wasn't to long.