i know that at my camp we are not allowed to tell ghost stories, even if the kids ask for them. because then a kid writes a letter home, "my counselor told me a really scary story and i had a really bad dream after." the kid might not have told you this b/c he or she was embarrassed to tell you b/c the other kids thought it was "cool" so you didn't know about the situation until the parents call camp and are wondering if their child is ok.
