My sister is comming to visit me

I am so uber happy and exicted cause sis has never come to visit before.
But...
She does not know about the SI. And she can
never know.
I love my sister, but she is so nice and sweet and innocent and light. Learning about the SI wouldn't make her hate me, but it would upset her and affect our relationship negatively. Shes too much of a light and happy person to be able to understand, and we'd end up becoming distant with one an other. So I'd still loose her and there is no way I can loose sis.
Shes staying with me for a week and we're gonna do loads of things together. It being summer too I can't wrap up without a comment when we go places. Eventually I fear she will see some of my scars. And then...
What do I tell her? I could just bite the bullet and mention before she comes that I have some scars. So that maybe she won't ask how I got them... But I don't want to tell her even that. I like that she doesn't know. I like how our friendship is now.
.gif)