I suspect my 12 year old daughter of suffering from Bipolar. She shows all the signs and her mother is also a sufferer although very mildly. It is proving difficult to get a GP or Social Worker to consider Bipolar as a reason for her behaviour. Is it likely to show at such a young age and what is the best course of action to take.
So sorry to hear about your daughter. This cannot be easy for you. Although I have never experienced it in a child, my ex-son-in-law had bipolar and it made our lives hell for a while. I think you might find this link helpful: http://www.bpkids.org/site/PageServer
It is a site in the US, but has lots of good advice. Best wishes for you and your family.