I think the posters who have responded raise a good question about what you should do now. If you cancel the boyfriend - is it possible that Carnival will say that there is no refund (because of being beyond final payment and type of booking) and Carnival also then wants to charge the daughter the single supplement - which is normally just a double fare on Carnival. This is why I use Bonnie - this would be her headache to find me the best solution in a situation like this.