ESH they suck, because they put the burden on just you to leave work. But honestly, I think you're all AHs (except your son, of course).

And of course your son is going to say "it's fine," when you ask him if he needs anyone to stay, he probably didn't want to be a burden. I think as far as being parents, you guys really dropped the ball big time here. It's not like you would be expected to leave work for the whole duration of the treatment, but both you & your husband should've taken some form of leave for some time, to put your full focus on your son who is going through cancer treatment for christ's sake!

I think it's kind of bonkers that people are saying you guys are at all right in this situation. What you guys did was kind of fucked up.