I am taking my daughter's friend along with us from New York to London for this event. Her parents bought the event ticket for her, so I have had to inform her of the odd fact that she has to bring some form of her parents' ID with her to use the ticket! I can't see them giving her a driver license, what about a photocopy? Is a credit card ok, and if so does it have to be the same one used to purchase the ticket? Any other forms of ID that would be acceptable and easier for them to entrust to their fifteen year old daughter?