I know how you feel-- I am also the oldest child and my parents made a lot of mistakes with me that they seem to have avoided more carefully ith my younger sister. It's frustrating and hurtful and infuriating, and yes my parents probably would have known better had they thought things through, but they didn't. The important thing is to stop caring about how badly they messed up (or continue to mess up) and to think about the person in this situation who is most relevent... you. Tough advice to follow, I need to do a better job myself :-P Also something to think about-- regarding what you may see as preferential treatment toward your brother: although it may be just that, I am reminded of a quote that made me look at my parents' relationship with my vs my sis in a new light: "Fairness is not about giving everyone the same thing, but about giving each person what they need." Just something to think about. Have a nice day :-)