Here's an interesting one for you all - just wondered whether anyone else has had any similar experiences, out of interest.
I've had Bertie, who's now 2.5 years old, since he was six weeks old. I got him and his sister Matilda - a gorgeous tortoiseshell cat - from the same litter and they were absolutely inseparable. Matilda was killed by a car when they were 11 months old, and Bertie and I were both devastated. I then got Bella from the Cats Protection League to keep Bertie company, and after a few initial wobbles, he seemed to be back to his old self within a month of Matilda's death.
It's now 18 months since she died, and last week, a new family moved into our street who have a tortoiseshell cat very similar to Matilda. At the weekend, I was woken by Bertie meowing at the back door, and couldn't initially work out what was wrong - then recognised the meow as one he used to do to get Matilda's attention, and which I haven't heard since Bella moved in with us. I went downstairs and saw that the tortoiseshell cat from over the road was in our garden and Bertie was meowing at her. I swear he thought he'd seen Matilda! My OH reckons I'm being mental and there's no way Bertie would still remember after this long - what do you think?