We are booked for May 2016 and we are taking our son(17) and our niece(13). Our son will have charging privileges linked to my cc but my niece's mom wants to have charges for our niece also and linked to her cc(so we do not have to cover it and then have her reimburse us, her preference). Is that possible? Or would it be best for her to get Maddy a pre-paid gift card for souvenirs(we are covering meals)? TIA!