There is little doubt that if Mrs. Paterson's Gilly hadn't cussed like a trooper that lost boy would have been denied his miracle. One librarian at a conference on children's literature in Virginia this summer speculated as to why parents react so forcefully to books they perceive as offensive. They see the books available to their children as an area where they can have control. Parents' attempts to protect their children from books that offend are misguided. For one thing, librarians say the primary effect of keeping kids from reading a book is that they want to read it above all others.
Children are tough and discriminating.
They hear language far worse than Gilly Hopkins' in the halls at school. Kids have eyes finely tuned for the subtle and are more capable of grasping complexity than most adults give them credit for. I read Black Beauty before I was twelve and learned a lot about compassion from it. I thought the Hardy Boys were sexist before I knew the word. And I knew Rudyard Kipling for a racist without having to be told by a well-meaning adult.