Stuck alone on Mars? I'd say that the "appropriate behavior" for that situation is pretty well undefined. It seems like a good opportunity for teachable moments

Stuck alone on Mars? I'd say that the "appropriate behavior" for that situation is pretty well undefined. It seems like a good opportunity for teachable moments: "Okay, Jenny, let's not use our Mars-language at the dinner table." If the parents and other authority figures in the child's life aren't already providing good models of social behavior, then the kid's got bigger problems to worry about than the rough language in the book, and if they do have good models, then I don't see the problem, as long as the context gets explained to them at some point.