I'm getting a bit concerned about dd (2). She seems to do a lot of teeth gritting and screeching noises, especially when she's tired. It's almost as if she can't help it and she just needs to let it out. I have heard that with tourettes syndrome tics are usually triggered by excitement, but it does seem to be over-tiredness with us. Does anyone else have any experience of this kind of thing? She doesn't have any facial tics, just this baring her teeth and strange noises from time to time.