texas montesorri schools

This question is for my daughter.  she works at a montessori school and her  2 1/2 yr old son goes also.  Her ex has two overnights during the week and 1,3, & 5 wknds.  Her son cries everytime he has to go with dad, who lives an hour away, they meet halfway,.  This is so sad and both mom and son are unhappy, I wouldn't think dad would like it much either, but he and his family are more into what is fair than what is best for child.  Anyway, in Texas after the child starts education, kindergarten then no more overnights during the week.  Well that is years away.  My question is, does a montessori school count as an educational "school".?  Could this be a loophole?   Thank all who can help or give advice!

Concerned mother and grandmother