Our cat has stopped making a proper miaow. He does it but it's much quieter than it was before. I've taken him to the vets who wasn't a bit worried about him. Says he's fit and healthy, although he's quite overweight and could do with losing a bit.
We rehomed him 13 years ago and the rescue thought he was about 18 months old so we think he's 14/15. Do they lose their miaow with age?