Fangcat left us a bit before her 20th birthday. She became talkative during her last year, it seemed she simply needed to know someone was around. If she came in from outside (she had a cat door) and couldn't see us, she'd howl until someone got in her line of sight. Same if she woke up and no one was in sight, she'd howl until one of us showed up. This was a bit of a problem in the middle of the night.
During her last year she also had two litter boxes. She became somewhat fussy about the facilities, using one for #2 and one for #1 only. She never pooed in the pee bin. And if we didn't clean her boxes twice a day, she expressed her displeasure by using the nearby floor.
Her last months she needed to pee every hour or so. So we travelled with three litter boxes - one in the truck for her to pee in when needed, and two in the fifth wheel - one for #2 and the other for #1, of course!