Crazy or just bad?

This Little girl went postal on her school bus. She attacked her bus driver and the police her mother says she gets a little mad when she doesn't have her medication. She is schizophrenic says her mother, but because of her great big outburst and violence she faces felony charges consisting of, battery on an officer, resisting arrest, and throwing a missule in an ocupied area. She was so upset and throwing such a fit in the police station that she was banging her head on the jail cell bars that the police had to use pepper spray on her to get her to stop hurting herself. The little girl is nine years old.
What I want to know is why did she not have her medication? If the mother knows she acts like this when she doesn't take it then why would she ever let her go without it? In my opinion and it is a little educated, my mother and sister are both child psychologists, this child can get upset without her medication however there is a level that most 9 year olds do not hit unless there are other underlying conditions that make her more upset than normal. All the medications do is even up the chemicals already in the body. They do not completly cure a child or make it where they are comotose other outside factors have more effects on a childs behavior than medication. She needs more supervision for her daily activities than what she is getting in my opinion, if this is not curbed now it will only get worse.