My little sister is so annoying?

My little sister is the exact same way. (She is 7, I`m 16.) When she is acting up, just ignore her. She only does these things to get a reaction, and your giving her exactly what she wants. I know its hard, sometimes you just want to beat the hell out of her, right? If your mom is not doing anything about the behavior of her child, then shame on her. If ignoring your sister does not work, then start giving her time-outs in her room, longer depending on how bad the offense to get her there was. The time-outs should not be longer then half an hour, though.