Even with bad genetics, would a 2 year olds teeth be rotting out of his head?

You could call the authorities if you think it is serious enough. When these children start school, the school will most likely step in, there is no reason for a 2 year olds teeth to be bad, they have only had them for a year or 18 months tops. Some medications can cause tooth decay but I highly doubt that she wouldnt be aware of that when given the prescription