Usually when we explain to the other kids that "Levi was just born that way and it doesn't hurt him. He can do everything you can." the other kids say, "Oh." And that is that.
We did have one little girl at my daughter's preschool ask about Levi's hand one day when we were dropping off in the morning. She asked Gloria if that was her little brother and Gloria said yes. Then the other girl asked, "What happened to his hand?" Gloria told her exactly the way I would have that he was born like that and there was nothing wrong with him. The other girl objected and said, "But I don't like his hand. It's scary."
Gloria in perfect and indignant form retorted, "It's not scary. It's just different. I have yellow hair and you have brown hair, but I don't say your hair is scary." I couldn't have said it better myself and the little girl never said another word about Levi's hand.
We've also taught our son to accept his difference and not to take himself too seriously for it. He's three now and it's starting to show. The other day, I saw him take a pair of my sewing scissors off a table in a room he knows is off limits. I took the scissors immediately and said, "Those are sharp. They could hurt you." Without thinking about it, I gave the classic mom line, "Do you still have all your fingers?" He started laughing and with a giant grin on his face said, "No. But I fine."
It's hard as a parent to know that he'll constantly cross paths with people who just don't get it or who are plain old mean, but it helps to know that he has such a strong sense of who he is and he has a sister who will stick up for him whether I'm there or not. And his sense of humor will break the ice for many uncomfortable people.