Heartbroken in In the Kingdom of Suzu

My daughter came over this afternoon to tell us that her daughters, my grands, PrincessL (14) and PrincessL (almost 11) told her that they don’t want to live with her anymore, they want to live full-time with their father and they became very disrespectful and ugly to my daughter. She ended up having them go with their dad but it is not over yet. In the summer they alternate weeks and since school is almost out, she just moved the summer arrangement up. Her ex is of course threatening to get the existing court order modified and plans on going to court Monday morning to get it changed. Hate to tell him that he can file all the motions he wants to the case will not be heard that day. A court date will be scheduled and then his motion will be heard. I know my ex SIL and I know he is behind all this. Ever since they were little, he has been working on them that he misses them, it would be so nice if they lived with him, etc. There is a whole lot more, but my heart is just broken. Thanks for letting me get this out.