When my elderly father had pneumonia he was convinced that burgulars had broken into the house and replaced all his possesions with fakes. On the phone he carefully explained to me that while there still was a television it wasn’t his television and so on. It was a terrifying conversation for me as I initially believed there had been a burgulary but it soon became apparent that the story made no sense at all. Luckily Dad’s neighbours had called in my brother and the doctor before he insisted on phoning me. Later on in the same illness he told us that aliens had visited the close and given presents to all the neighbours but he hadn’t got any. Poor Dad.