Although I totally agree with them not attending (and, really, THEY should have called and uninvited themselves), maybe the way you handled delivering the message was a bit unfeeling. Your sense of humor aside (and gotta say, I kinda have a similar weird sense of humor, so I get it), how would you have felt if your son was really sick, you're worried about him, worried your other child will also get sick, etc. and you get this lighthearted, jokey text (not even a personal phone call) about being uninvited? Probably a better way would have been a phone call to 1) check up on the child and show your concern for his illness 2) discuss why you can't have them at the party and 3) let them know that you'd love to celebrate with them another time when the son gets better. I can see how the other mother's feelings were really hurt, not because of you not wanting them at the party but because of the way you uninvited them. I know I would be hurt. So you get an A+ for keeping them from infecting your other guests, but a D for compassion. ;-)