The one family didn’t have manners enough to RSVP their change in attendance and the other family doesn’t have the manners to let it go. While the ski trip did cost money, they were willing to pay it if the kid were there. There would be fewer conflicts of kids were taught etiquette in school. Not to force them to act certain ways but so that they would know how to handle situations. And yes, I’m meaning that the parents should have been taught it when they were in school.