Cass sighed. "People do, and you might, but you should not assume it," he said, feeling his throat constrict at the thought that his son might feel the same way. "And surely there are better things to do with your time than running around hitting people? Even people like Pettigrew?"
"I'm not saying be nice to him. Ignore him. Or at least make sure you're not seen and that you have back-up so you don't get injured."