This sucks so much. Those poor little babies. I can't IMAGINE leaving my kids anywhere without me when they are that sick. So sorry they were thoughtless enough to spread their illness to you and your family. Regardless of when they were contagious, you don't take a sick kid to daycare! They slow/halt the group, and doesn't everyone (my own 40 yo self included) just want mama when they're feeling crappy?? In my opinion, this goes beyond being a bad daycare family, and moves into the realm of poor parenting.

I can't believe her gall to be angry at you for taking the day off with an illness that she directly caused. This is like her crashing into your car, and being angry that you can't drive her to the airport. I had a family do this to me once. Mom sent dcb with a horrible rash, knew it, said it was from his vaccinations, and gave everyone in my daycare hand foot and mouth disease, then got angry at me for shutting down for two days when my own son got it. Sometimes there's just no accounting for the actions of others. We have to buck up and move on...