You thought you knew what was expected but now you don’t. Your parents read a good book or they go to a parenting class and they change their expectations. Then there are the parent-stepparent changes. For years you could be sarcastic with your brothers and then a stepparent enters the scene and takes it personally when you’re sarcastic with your stepbrother. It’s a pain. And it would help if they wouldn’t take things quite so personally, but maybe you’re going to have to stop being sarcastic.