I hadn't even thought about CPS. Thanks for the suggestion. I'll bring it up with my best friend and her husband and see what they think.
Years ago, I listened to a parent horribly verbally abuse his son on a basketball court outside my classroom window. I had no idea who they were, but the school nurse was able to figure it out from my description. She had me call CPS, and they made a visit to the home. They did a good job of handling it. Calling them in this case is a great idea.