Parents who don't follow the policies and work against us will always argue when a specific reason is given. i.e. if you mention her coming when ill, the mom will try and reason that she wasn't to know etc. Since you aren't going to change your mind, the reason is irrelevant so it's better not to try and justify your reasons. If she was handing you notice, you wouldn't be quizzing her on the why, you'd be accepting that your service no longer meets their needs.

Just put that unfortunately you have made the decision to give her notice, make sure you detail the final date of care along with any dates during the notice period that fees are due. If you have a policy that they pay regardless of attendance during the notice period, remind her of that too. Attach a signed copy of the contract to remind her that's what she agreed to.

You will always feel guilty but you shouldn't. This isn't a friend although I know when we love the children, it's hard to remember this is a business transaction. This parent isn't a good match for your group. It's better to give notice to one client than risk losing more than one of the other client's because parents are fed up with their children being exposed to illness they shouldn't have been or the lack of a quality rest period which is key in their development. A bad apple in the crate never ever learns from the good apples. A bad apple will always contaminant those around them so remove them fast before the rest of the container rots.