The Unlimited Festival Resources

hello…our 13 yr old daughter has been “acting” up terribly…the last couple of semesters she has been failing a lot of her classes…she ran up hundreds of dollars on her cell phone with downloads…she made over 3,500 text messages in one month…(we took text messaging off of her phone and take the phone from her when she gets home from school)…she impersonated her mother and emailed her teachers asking if “her daughter” could do extra credit to make up her failing grades…we let her go to what we were told was a “christian rock festival”, but we later found out that it was a thrash metal concert called “bledfest”…(we will make sure that doesn’t happen again)…she is constantly lying, backtalking, and not doing anything we ask of her…she has done a lot more things, but i tell you a few to shorten this question out…tonight i am especially worried…she used the computer in the den…when i went on to use it afterwards i had seen she had left her myspace page up…on that page she said she is “98″…also she put down that she smokes and drinks…she had a picture with her step sisters that are in there early 20’s…under the pic it said “can you beleive that we get f’d up?”…in another pic she makes a reference about pot…and everything she talks about on it she writes the “f” word every other word…should i be worried that our 13 yr old is doing drugs?…we have let her spend a lot of time with her sisters and with her mothers ex husbands family…oh, one of those sisters is in and out of jail for many things including pot busts…what do we need to do to get her back on the right track?…would it be wrong to stop her from spending weekends with some of her family that could be getting her into drugs or situations that a 13 yr old should not be in?…i want to start being “strict” with her…her mother wants her to have her “freedoms” and let her learn from her own mistakes…what should we do as parents to fix some of these problems?…