You have a situation many of us have been in. I have tried telling my family about HIPAA and that has not gone over well. I guess I could have told them nothing she is still resting at home. It would not have mattered. In your case it may not be that easy because they may want to visit no matter how sick she is.

Have you considered asking your daughter to come up with a story that works for her? That would be best to get her to make it up if she feels up to it.

The other thing you could tell them she has a brain disease and they are keeping her in isolation to make sure no infection happens. This is true in that all mental illness is a brain disease. She won't be able to have visitors for approximately 1-2 weeks. You probably don't want her overwhelmed with visitors the first few days back.

In any case clear it with your daughter if you are able to.