The best advice I can give you is to deal with this now. I lost all my weight when I was your age, from 215 to 135 and then I regained it. 20 years later, I'm at 215 (and that's a good place today).

You have your whole life ahead of you, don't waste it worrying about your weight like I did. Fix this now while you have the chance.

And that pretty sister (I have one too, same thing exactly) well, just keep telling yourself that one day, the boy she likes, will have a crush on you because you'll be so hot!! You can do it!

Valerie