So it did not worry you then that your Dad might kill someone while behind the wheel? My late Dad became unfit to drive due to onset of mild dementia. He nearly killed me a couple of times. He did not realise that his driving was erratic and thought he was fine in all respects but we knew that he was not so we told his GP (admittedly, behind his back) as I could not have lived with myself if he had harmed someone. He had to undergo a driving test which he failed and therefore lost his licence and he was extremely upset about it for a while but he soon adapted and no longer even missed the car.