Has anyone else in the Famil;y not liked Bugs? or a Baby sitter or firends, very often this is a behavior that has been exhibited by another Family Member, and they copy,The noises some children dont like, when she does it do you reamark to her a lot about it,small children often do have little Phobias, play it down and see if you ignore the Behavior if it will lesson.couls she possibly do it to get a reaction.