How to handle what might be a petty theft at NH?

My mother was very upset this morning because she is convinced someone pilfered her hearing aid batteries from a little bowl she keeps in her bedside drawer. She has to change them every other day or so.

I had brought several packets of them so she now has plenty. But she was so upset that this happened and wouldn’t let it go.

She thinks the night staff is doing this but really there is no way of knowing. I was trying to keep things light and kept changing the subject.

It does not seem worthwhile to make a big deal about this and complain to the staff, but I don’t want my mother feeling I’m blowing off her concerns.

Anyone have thoughts? I do not think she has dementia, if she does this would be the first sign.