Those jonas brothers!?

my daughter, maeby, recently discovered the jonas brothers! (the homely one is her favorite) however, i made a huge mistake and trusted her! she lied to me! she told me that she was going to "buy one of those necklaces with the t on them" with her cousin. later on i discovered that she went to the concert, alone!!!!! she even tried to get backstage!!!! WHAT SHOULD I DO?!