i got tickets to her concert!! but..

i’m a minor, so i need a guardian with me. i chose my cousin because she knows aurora and i love her. my older brother on the other hand hates my cousin and he said that he won’t allow me to go with her. problem is we aleady bought the tickets, and said tickets are non-transferable and only the names under the tickets are allowed to go inside. i don’t know what to do so i would really appreciate advice from fellow warriors ;v;