What can you do to stop bullying your sister?

Nobody should be bullying your sister or brother. if a jerk does decide to bully a sibing of yours, you shouldn't hit them if they are younger but to yell at them so they know never to mess with your sister/brother. Yell at them and call them names and give them a warning or threat like: "Next time you mess with my sister i will come in here and fight you like a cantalope!" haha