As for the thrush--Sometimes when a person takes too many antibiotics (if the child has been on any) they can kill off the good bacteria in the mouth as well as the bad, thus causing the
thrush infection to grow. The more antibiotics you take for
thrush, the worse it gets. Antifungal medication such as nystatin is usually a good medication to take. For children it comes in a liquidy solution that taste a lot like bananas. This medication is also called "swish and swallow".