IIRC An IEP (individual Education Plan) is created for each special needs child before entry into a school. The IEP outlines what services are to be provided and who is responsible. Some schools have aids that are responsible for feeding, changing, etc.. Others have the school nurse do it, depending on the number of students in the population.
If this is in the IEP then the mother doesn't have a leg to stand on, and I can't imagine a school that would not have an IEP for a five year old still wearing diapers.
IIRC An IEP (individual Education Plan)?
It seems like this should include and inform the parents also. PTA used to be meetings with teachers where parents and teachers worked together. Now it seems that the feral government has gone wild in a power grab and edge parents out of education.