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my sister has this guy friend who is in super love with her, like in a creepy way, and she is trying to be nice And say that they should stay friends right now, but he says he can only think about her and he needs her. as the older brother what can i do to protect her, im very tempted to face him and knock some sense into him! the hard thing is she hasnt told my parents this or me i just hear from other people and text messages she gets on facebook. what should i do?