my other sister is so mean with me.....

Ask her why she is being mean to you and tell her that you are bothered by it. If she tells you why then you two can patch things up immediately. If she does'nt tell you or gives a vague explanation then don't lose sleep over it. It's a natural phase that siblings go through. She'll get over it in due time. Meantime, be the mature sibling and don't retaliate. It is hard at first, but eventually you'll get the hang of it. :)

hey dude she is your sister so don't even think that you should behave same as she is doing to you .it might be that she is not mature enough to understand the feeling of a brother for a sister but one day she will be able to understand your feelings.so try to make a place in your sisters heart by your kind support to her.don't even think of taking revenge because a friend can be replaced by a friend but what can be the option for own sister.best of luck

NO, dont be mean back thats most likely what she wants, be the better person and say he look i have always tried to get along with you and never change that you know in your heart that you have always tried to go out of your way to make things work and thats all you can do, You will find someone who deserves it if you keep trying if she doesn't come around its her loss!