Please take your brother to the prosecutor and wherever you need too in order to obtain a restraining order. This kid is dangerous. A restraining order won't keep him away but is legal proof of your brothers intentions to not be harrassed. I work with special needs middle schoolers and they can be violent at the drop of a hat. Don't delay in taking action. I don't want to frighten you and certainly would never want to get an innocent child in trouble with the law, but this is not the innocent acts of a child. His lying lets those around know that he is aware that his actions are wrong. Pleae protect your brother and other students by pursuing this, the school will try not to get too involved but you must keep after them and log every encounter and photograph all physical evidence. Do not depend on others wanting to get involved from the school---they are probably afraid of him and his ability to make their life miserable. Make a police report of every incident just for a paper trail. This student is a danger to you and your family. He is deeply disturbed and needs professional help.

good answer, then spend time with kiddos.