It isn't certain, but since the strap was usually made of goat-skin, it could have been a symbol of fertility. By striking the women (often on the wrists) with it, it was said to ensure fertility, easy childbirth, and good health for them.
yes, because she's recording it without her dad's consent. her dad might not want her to show it to anyone. confronting her before anything gets out of hand is the best thing to do.