Dear friend,
Whenever a formerly clean cat begins to soil out of box I am going to susupect a health issue. Cats are very smart and they often "talk" with their waste. Your older girl is not feelig fell and she is trying to "communicate" her discomfort.
At 15 it is common for diabetes, liver, kidney. pancreatic or hormonal issues to develope. Dental problems like abscessed teeth or gingivitis are also possible.
Please have your girl seen by her veterinarian and some bloodwork done so you can see what is going on with her. Most disorders of the older cat are now highly treatable but early diagnosis and treatment is imperative.
Please let me know what was wrong and how your girl is doing. If you have any more questions - I will be happy to help in any way possible.
Very sincerely,
Terri
Dedicated to Cats and the people who love them!
Please press ACCEPT if my answer was helpful and leave feedback Thank you! Terri