Hello. I'm new to this forum and I've come looking for some help and advice about my Dad. My Mum and Dad live together- she's 60 and he's 85. Over the last few years he seems to be becoming extremely paranoid. Mum works, she does long 12 hour shifts a couple of days a week. He needs her to ring him every few hours and is very suspicious about where she 'really' is. He checks her pay slips and has called her office before to check she's really at work. A couple of months back he got a taxi to her work to check her car was there. Last night she was due to finish a little later and told him. After work she tried to ring to say she was setting off but no answer. She pulled over a couple of times on route but still no answer. When she got home she got out of the car and suddenly the back for opened and he got out, laughing. He'd been sat in her car the whole time?! To my knowledge Mum has never cheated on him so I can't understand this paranoia. However I recently found out that he has children younger than me and has kept them secret from us all. In the back of my mind I can't help but think that this is what is causing him to be so paranoid? I haven't told Mum about this as I don't know how to. Additionally his memory is going- he will repeat himself and is generally confused by normal every day things (still can't use the sky remote correctly, forgets what I do for a living for example). Are these things suggestive of dementia? I don't think my Mum can handle it anymore.