My sister thinks I am soo uncool, how do I make it stop?!

My sister thinks I am soo uncool, how do I make it stop?

My sister is two years younger than I am. I am in grade 9 and she is in grade 7. She all of a sudden thinks she is is just so cool and I am just so not. She says stuff like "Thats gnarly," and when I have no idea what she is trying to say, she just says I must not be cool. I don't really care what a seventh grader thinks of me, I just hate how she has such a big ego and everything I do is considered uncool. She judges me on everything from what music I listen to, what books I read, if I do my homework, or what I wear. I am not uncool, I have tons of friends and I am smart and responsible. I just don't care what other people think of me. Although I do care what my own sister thinks of me.

Haha, I think thats funny. "Thats gnarly"? Who the hell says that anymore? Tell her shes uncool. Fight back with her. Seriously, all sevies are retards, you aren't ever cool until after 9th grade, but a freshman is still cooler than a seventh grader anyday