Aw, come on Dr. Hojo, his self-worth may be stunted as hell but he'd understand you being down about losing an earring during the dolphin show. He can't exactly blame that on his older brother, after all.
MC's 'plight' may seem a bit exaggerated, but that's a real type of learned internal conflict. Always thinking of yourself as in the shadow of someone harder, better, faster, and stronger, especially if they're your brother or friend, if not best friend in my case, can leave you with some pretty screwy confidence levels. I was often used as a stepping stone by girls to get to my best pal in the next grade up. My first two serious relationships were often punctuated with, "Quit comparing yourself to that guy," followed by a sentiment that isn't unlike Nukumizu's Puppet Pals' "this part of you is no good" retorts. It can be a difficult wall to get over. Nobody said loving yourself was easy - that's just for narcissists, and even then that's less 'self-love' and more 'I'd fuck over my own mother without hesitation to avoid the mildest of consequences.'