You say your family life is not healthy then i would strongly suggest family counseling. Working together as a family will show your daughter that you are there for her and isn't being singled out as the "problem". This way her self esteem does not suffer. Often the group approach works best in this situation, a breathe of fresh air for the whole family.

Her hormones could be affecting her. She may only be 9, but girls do develop more quickly these days. My eldest started at around 9. Other kids at school often don't help. If she has a friend who does the things you say she is doing she is likely to copy. Peer pressure is a bugger!

Is she happy at school? Often kids have problems they don't talk about. Ask her how she feels about school, about her teacher, the other kids. Remind her that she can tell you anything & will not get into trouble, you just want to help her.

Look up www.michaelcarr-gregg.com.au - he is a leading pyschologist who has done a lot of work with kids. He has many books out that may help you.