Just to update I was at my house yesterday and I cleaned the kitchen and the bathroom they used, with the exception of the toilet, I dumped bleach in it and told asked my sister to clean it. Everything I cleaned was with lots of bleach. I left after that I still feel quite anxious about going home since when they were sick they were on my couch and really all over the house. It's been about 9 days since they started feeling better and 11 since they first got sick.
I feel crazy but don't want to have made it this far just to catch it from something on the surfaces.
I read online the norovirus can live 2 weeks on surfaces and probably forever in the ffreezer, when my sister was sick she was in and out of the freezer getting freeze pops. Now I'm afraid of touching everything in there.