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We wondered if he'd remember anything after all that time, prudie - but when we went to collect him from the vet, he looked a bit blank at first, but once he'd had a good sniff at OH, he came bounding back, I am sure they go on scent rather than sight. He's settled back into a routine much the same as before. It's so hard to say - we know how we'd react, but a cat mind is very different!
It's really hard for me when I go out now, to realise that I can stop looking under bushes and in hedges, he's home!