I dont think there will be any problem in changing the name of a guest who is not the lead guest on a reservation. As The Mom said people change their names for all different reasons, so this shouldn't be a big deal. Just be sure to book the trip under the name they will have on their ID at the time of the trip, For example, I advise that if you are booking a honeymoon trip, right after the wedding, that the bride use her maiden name for that trip as that is the name she will have on all of her ID within a few days of the wedding. Have a great time!! Marie