I'm almost positive my mom likes my sister more than me?

I'm thirteen and my parents are the same way though my parents are together. My brother is twelve years old. He's obese, constantly playing video games, the list goes on and on but gets good grades which wins my parents over every time. He fails to think things through and I don think he'll amount to much in life and my predictions come true. I've written two books, taught myself Greek, am a skilled artist and alot of stuff (though I haven't told them yet). The way I see it is that I'll do something important in the future while my brother fails. I want them to be surprised at my genius and regret bragging about my brothers straight a's. I've always had things harder. Then they'll wonder what happened to their perfect child and realize I was the perfect one all along