If she knows this bothers you and is still doing it, she is being disrespectful and mischievous. If you have already told her several times and she continues to brush it off, plan on sitting her down in a more serious manner and let her know that this truly bothers you. Perhaps come up with some kind of a consequence by saying something like "If you do it again,...then...I will do....(whatever it is that she will find unpleasant)" Find out why she is still doing it despite the fact that she knows it bothers you. If you think that she is not doing it on purpose, maybe try to ignore it a few times. She may be doing it just to get a reaction out of you.