Bonnie (my foster cat) bites when she gets excited. It is usually when playing or after being petted. I have been telling her "NO biting" and take my hand away, but I want to be able to teach her not to do this so that when she gets a home they do not return her with the lable NASTY. She is in no way vicious, but it would not be good for her to go around biting at the hand that feeds even if she thinks she is playing. Has anyone dealt with this?