Imagine you are on the holiday trip of your life - south italy, just across Sicily. Your'e in a bar, there's this incredible girl with piercing black eyes, and you don't know if she just smiles at your veiled attempts to explain the bartender what you'd like to drink, or just smiles at you.
To break the ice, you scratch together your last italian, and say something to her.
In that moment, the whole bustling location freezes. Eyes either turn to you, or away. The bartender slowly puts down the bottle of whatever you did not want to order, but finally agreed on. A young italian boy, slender, moving like quicksilver, dark, angry eyes, turns around and asks you (in unintelligible italian, of course):
"What did you just say to my little kid sister?"
THIS is the kid sister rule.
we are here to help each other get through this thing, whatever it is Vonnegut jr.