My cat (neutered tom, 12 years old) has started spraying indoors recently (over the last month or so) - he backs up to something, tail twitching and sprays, sometimes just a little bit, sometimes more. He doesn't just do it in one part of the house - all the rooms, all the surfaces. It's a daily occurrence and it's now officially driving me up the wall! Nothing has changed, as far as I can tell, to make him upset or nervous. He is old, but healthy and active. He is still going outside as much as he did and I've seen him peeing and pooing outside, so it''s not because he doesn't want to pee outside.
Does anyone have any advice? Am I missing something? Can this sort of thing be solved? Might it be an illness? In all other ways he is a perfect cat, great with the children and very friendly, but my youngest is a year old and I really don't want her wandering through pools of cat pee!