Diaper changes on special needs students

I have no problem helping out when I am on campus. My problem is that "nobody" else in the entire buliding will serve as an emergency back up. We are talking about having to step up probably less than 5 times in an entire school year.

It is the resposibility of the entire staff to provide for the comfort of this student and not just the nurse!

Certainly, I cannot get in the car and travel 40 miles while on maternity leave post c/section to change this poor child! Yet, my principal is insinuating that by going on maternity leave - I am ignoring my duties! Therefore, she feels the nurse at he junior high who has over 1200 high needs students and is emergency coverage for 3 other schools needs to drop everything and become responsible for the task.