This was left in the comments to Aunt Babz...
I'm really sorry to hear that you're going through this. You are not alone. This is the third letter in a month or so, that I've received concerning this violent behavior by a sibling.
This issue is not new, as I can remember when I was a kid, my best friends brother, smacked her around all the time. We plotted to get him back, I don't know how many times and eventually, we did some less than savory things to him.
There was a time, when I would've told you to pick up a bat and smack the day lights outa him. But I have learned violence begets violence. In this life though, if you allow yourself to be a victim, you will be. You must take charge of the situation. What can you do?
I wrote another post, Revisited; Zero Tolerance for Violence.
Read this and take what you can from it. If possible, either send the link to both posts, to your parents. If that doesn't work, speak to your Guidance Counselor. Holding it all in, is not good, either. But the problem is and lies in the fact that you are allowing yourself to be a victim. You have to remember that, your parents probably don't realize just how much of a problem this is, to you. After all, I doubt seriously, if they've seen your brother do what he does best. So, they probably figure it's just kids being kids and dismiss it. If you don't assert, what's really going on and tell them how it affecting you, it will continue.
Just as I said, in the other post, I will say to you; Try to speak with your parents and you must let them know about it all. You must make them understand, just how bad this is. If you feel you can't do that, the next time your brother starts, you tell him, you are going to call the police. You tell him, if he comes near you again, you will call the police. Pick up the phone and maybe he'll stop.
I feel because of the nature of this, that you should print the posts out and give them to your parents. If you can't do that, email the links, so they can read them. Here's the links, you copy and paste them in the email. Just say, please read;
If you feel that distant, from your parents, that you feel you can't send them these posts or talk to them, you can at least tell your brother that you will call the police. If he hurts you again, make the call. It is illegal, for him to lay one finger on you. Remember that. The police will address the issue.
You've got to realize that no matter how bad you can't see it, you always have choices. They are there, you must trust that they are there and look for them.
The first choice is to stop crying about this. Dry your eyes, sit up and say, "I'm not going to be a victim here, anymore." Don't be afraid to tell your parents, how serious this is. The second choice is to take action. Follow through and call the police. I doubt seriously, they would take him away but it would possibly scare the crap out of him.
You said, "I want to tell someone but am afraid." Afraid of what? My dear, you are setting yourself up, in the future, to be the kind of woman that suffers in silence, when her husband beats her. You can't see this but I can. Been there, done that. It has to be Zero Tolerance for Violence. He does not have the right and should never lay a finger on you. It is wrong, it is illegal and you'd be doing him a favor, if you stop his behavior, now! Think of it as an Intervention.
Stop allowing this. Stop being a Victim. Take Action!