A cat who used her tray perfectly for years and has started missing it is telling you something has changed, and the change is almost never attitude. Her body, her senses or her memory are not doing what they did, and your job splits into two halves that run together: make success as easy as possible for her at home, and get the underlying possibilities in front of a vet. Blame has no part in either half, because she would use the tray if reaching it, entering it and remembering it were all still simple.
Access: Low Sides, Short Distances, Her Own Level
Begin with the tray itself. A high-sided box that she once hopped into can become a genuine obstacle to stiff hips and shoulders, so offer a tray with one low entry side she can step over without lifting herself, filled with litter that feels soft and familiar under her paws. Keep the litter type and depth unchanged for now, unscented and fine, because she does not need a new texture puzzle added to an old problem. Add trays instead of relocating her usual one: one on every floor she uses, placed where she actually spends her hours, and never somewhere she must pass another pet, a noisy appliance or a long dark corridor to reach. A night light along her route helps a cat whose eyesight is not what it was, and a washable mat under and around each tray turns a near miss into a small laundry job.
The Possibilities a Vet Will Investigate
Book the check promptly rather than waiting to see, and treat a sudden change as a reason to be seen quickly. In a cat with her history, a vet will want to explore several possibilities, and it matters to hold them as possibilities rather than jumping to the one you fear most. Stiff, painful joints can make climbing into a tray, and posturing in it, genuinely hard. Changes in her brain and memory can leave her unsure where the tray is, or aware too late. Urinary problems can shorten the warning she gets and make urgency beat distance, and increased urination from other causes can outrun a one-tray household. Constipation, eyesight loss and general frailty belong on the list. Take your accident notes along: where she goes instead, at what times, whether she reaches the tray and misses or never sets out for it, and whether her urine volumes or habits look different. That pattern is diagnostic gold, far more useful than a general report of unreliability.
Cleaning Up Without Punishment, Ever
Clean every accident calmly and thoroughly, with no comment directed at her at all. She is not being lazy, spiteful or senile on purpose, and a cat scolded near a tray learns to associate the tray area with trouble, which makes the whole problem worse and can push her to hide her toileting elsewhere. Enzymatic cleaning of the accident spot matters practically, because a surface still smelling of urine to her sensitive nose keeps inviting reuse. If she has chosen one wrong place repeatedly, try placing a tray exactly there once the area is clean; meeting her where she already goes often succeeds faster than persuading her back across the house.
Adjusting the Household Around Her
Once the vet picture is clearer, settle the changes that help her into routine: trays stay where they are permanently, scooped often so she never faces a soiled tray, and litter levels kept consistent. If her mobility is the issue, a step or ramp to anything she still loves is kinder than expecting her to give it up, and essentials on one level, food, water, bed and tray in the same broad area, reduce the journeys she must plan. Revisit the arrangement as she changes, because a setup that suits her this year may need shortening again next year. Keep the record straight as you go, and that record-keeping is precisely the everyday work a Pet Passport holds together for her, with accident patterns, vet findings and tray changes in one file that KinsLe keeps current.