Aww that sucks! But your sisters wedding (hopefully) will only happen 1 time, WCBF happens every year. There'* always next year buddy! I'm a girl and if I had a brother and he didnt come to my wedding because of a car meet, Id be PISSED!
Sweetie, as much as I know how much you love going to the WCBF, I know that you love your family more. You have to go your sisters wedding, and for all those who say you should go to WCBF, well they are wrong. There is really no other choice. I know you will be missed.