Back in 2006 my niece was married in Paris and asked that I bring my kilt along for the event at the ritz. If I recall correctly I used my kilt roll for the kilt and carried it on. I think that the jacket and the girls dresses (my two teenage daughters came as well) went in a garment bag just a thin one again as carry on. If you have a real solid garment bag that folds in half that should do the trick also. I would strongly recommend doing carry on for the important items for the wedding, don't want that stuff getting lost by the airline.