Tell her the car is outside, just keep the car, but give her the keys. This gives her a sense of control, but she will not fine the car if she were to look for it.

I know this sounds deceptive but disable the car but let her know her car is back. Al least she won’t be able to drive it and she might be content knowing she got the car back.

Thank you everyone. Your answers so far have been helpful. I have called her neurologist's office to talk about anti-anxiety medicine.

Update on mom. Sister took her to DMV yestetday. DMV asked her to take a driving test. She did not pass. Was very angry. She thinks my sister and I did something. We just alerted them she has a medical review form on file. But she had to call my sister to ask what her address was while with examiner. She demanded the key. Said she hated us. Don’t come ever again. Mom has the key but we are getting a new key and adding a battery switch so we can turn it off when we are not using it. Our visits agitate our mom so we will leave it to her caregivers for what she needs. We use Amazon to mail her things she needs. Otherwise, we are leaving her alone. She is nice to everyone else. This disease is awful. I no longer have a mother. Just a mean rude person.

My siblings go thru this daily about the car. Our mom is 91 and her doctor said no driving!!! She gets SO angry!! She can't remember what happened two minutes ago but never forgets that car!!