If you feel that they really need to know then don't use names, as something like. Due to an incident with a pass daycare family/child (this doesn't mean it was the one who just left) the following changes have been made. Please rest a sure all issues have been resolved and I have put these changes in effect to insure the issues do not reoccur. Keep the story about the incident/issues brief and to the point. Let them know that you want to protect the confidentiality of the other parties involved. This will re a sure the new family that you will protect theirs as well.