My husband ex wife never shows up on time for visitation but turns around and shows up unannounced at our home?

Ive been with my husband 7 yrs and I'm so sick of his ex. I have tried my best to deal with his ex but she is irresponsible and disrupts our life every chance she gets. Yesterday she just showed up at my door asking to take my stepdaughter to a ballgame. Well fine but could she at least let someone know? Her visitation starts 5:30 on friday but 9 times out of 10 she doesn't show. Of course she didn't show today and my husband texted her saying to call in the morning before she comes and he will meet her. Her response was no she'll see him in the am. Last week she did the same thing and when we woke up the kids just werent here. She came by the house and didn't even let anybody know she took them. The kids have been picking up on her attitude and Im sick of dealing with this every week. Is their anything we can do aside from going to court?