Don’t talk back to your parents or teachers. Politely argue if problems come up but otherwise do what you’re told and show your sibling how it’s done.
Boys who witness their parents being violent are twice as likely to be violent themselves, so what do you think they’ll do if they see a brother that they really look up to being violent?
You should also build their trust by creating a safe place for them to come and talk about their problems. You should never laugh at them or judge them for the things they say to you, so that they know they can always come to you without fear of how you’ll react.
Seeing things from their perspective can also be done every day. Appreciating their struggles in life and respecting them for what they go through will give you both a better respect for the other.
However, if they refuse your help, you need to respect their wishes. If they really want to try to do things on their own, the best you can do is to be there for them if they fail or need help still.
