Probably good to figure this all out or tough it out for the remainder of the maternity leave. I only suggest they go to the principal IF a consensus can not be reached between the two of them.

Believe it or not, the teacher isn't going to be able to put in as many hours as she did before the baby. Having been there, done that, she'll be out the door herself at the end of the day! I had a major rush to get to my baby (nursing reasons, ahem) by 4pm each day. Before baby, I worked late every night.

This parapro might have to be very flexible this entire school year...