The worst for me is that the kids consistently forget stuff at her house.
I had a talk with my kids and told them they need to be experts at packing and moving the stuff back and forth. They are in charge of their stuff, not me, no their mother. They learned pretty quick not to leave things. If it was schoolwork, it was a big "energy drain" for me to help them go get it. Anything else, had to wait until the next exchange.
Parenting with love and Logic" was a good foundation for my parenting style. The "energy drain" statement to the children was great. Any thing that drained my energy made it extremely difficult do do things they wanted. "I don't know if I will have enough energy to take you to your friends birthday party" or "I don't know if I will have enough energy to allow your friends to spend the night" etc.
"What is best for my kids is best for me" Amor Fati Link to quotes: https://www.divorcebusting.com/forums/ubbthreads.php?ubb=showflat&Number=2879712