I've had Remy for 10 years, he came from a rescue and wasn't a kitten when I got him. I'd estimate him to be around 12/13. In the past 10 years he's had fits on 3-4 occasions. They don't last long, he's seen the vet and no obvious cause. Most recently he had one last week. Since then he's become extremely aggressive towards one of my other cats, seems to have lost his appetite and general enthusiasm for anything. I'm planning to get him to the vet tomorrow but I'm wondering if it could be senility or something brain related? He's always been the most laid back cat, has never been one to fight, or scratch/bite, so to see him so aggressive is quite concerning. Any advice?