What would be the repercussions if Laura took the kids and moved abruptly back to Illinois?

In today’s edition of Is This Real Life? featuring asshat extraordinaire Skeeven, I’m brought to a very real question. At this point, with how erratic S is, I hold some genuine concerns as to how he might act out now that another court date is looming in the horizon. L’s mom seemed to be gently nudging L to come back home to be closer to her family during all of this. Since L has the DVRO in place that gives her temporary sole custody, would it be possible for her to take the kids and move to Illinois between now and the next hearing? I’m sure it wouldn’t be permissible but I also can’t find a direct answer as I’m searching the internet. If she did translocate and made a plea that she was scared for the lives of herself and her family as well as needing the familial support network to get through this trying time, what would be the repercussions? Could she be compelled back to California with the children? Would it become a jurisdiction issue? Genuinely asking for insight on this.