I dont know as I am still technically a child myself. However, I think the best thing to do is not act like its some bad thing. I mean it is, but by skirting around the issue and making up things, they will learn that a stigma comes with the scars. I would be open about it, educate them about it (so that they know that it's not a good idea), but don't hide. They are part of your story and I don't think u should hide it.