Hi there and thank you for writing to me.
Can I just say that it's really good that you're looking out for your sister. Bullying is a really difficult thing for anyone to deal with. It can feel a bit easier if someone understands what's happening.
I know your sister has asked you not to tell anyone but I'm glad that you have told me. Bullying is such a problem for lots of young people and for some adults too!
I don't have any easy answers, in fact I don't think anyone has. What I do know is that sometimes talking the problem over with someone can really help. For some people it will help them decide what to do about it. You or your sister can talk to one of the counsellors at ChildLine about this.
We hear from lots of young people about bullying so they'll know exactly what you're going through. They won't tell anyone about the bullying so you don't have to worry about that.
You can call ChildLine on 0800 1111 for free. If you prefer going online you can chat to a counsellor on the ChildLine website in a 1-2-1 chat, just log in and go in the waiting room for a chat.
You could also have a look at what other young people are saying about bullying on the ChildLine message boards.
It's good that you're helping your sister but don't forget that ChildLine is there to help you too!
Take care
Sam