maverick - I got back into wrestling (after a 35 year break) because my daughter got involved. It really makes me happy to see your sister enjoying the sport - and doing so well.
Part of wrestling is injuries. Hopefully, all of your's will be things like black eyes. (I was always, secretly, a little proud of things like that. They made me feel kind of tough!) Sometimes the injuries are a bit worse. Stay in good physical condition. Stretch carefully and thoroughly before matches. Make sure your technique is good. That will keep you away from the really bad injuries. Meanwhile, show off the black eyes and the bruises. Whimps don't get them! (Some of my worst bruises were put on me by my daughter - and she loved it!)