Liz,
Do you know if this DD ever talked to the school pyschologist? It's very difficult for children when the parents are divorcing. I know it's been 4 years, but did this daughter ever speak to someone. I'm only saying this because when my "crazy" daughter told me she was filing for a divorce, I did advise her to let the school know, "just in case" they started to act up in school, or their schoolwork got behind a bit.
My "crazy" daughter told me that both her boys are just fine with her, but when they go to their dads house they both act up over there. That's only hearsay from her, my son told me different. Her youngest son acts up when he is with my daughter, and her older son acts up when he is with his father.
Take care
((((((((((((hugs))))))))))))
amy