Senior cats hide illness even more effectively than senior dogs, and the signs that matter most are exactly the ones easiest to write off as "just getting older" — drinking a bit more, slightly bigger litter clumps, a little less interested in food. None of it looks urgent day to day. Together, over a stay, it can be an early sign of something that genuinely needs a vet.
The short answer
The two things most worth tracking in a senior cat are water intake and litter box output, because early kidney disease — extremely common in older cats — shows up in exactly those two places long before a cat looks obviously unwell. Tell your sitter what's normal for your cat now, so they can actually notice if it changes during the stay.
Kidney disease: what to watch for
Chronic kidney disease is one of the most common conditions in older cats, and it develops gradually — a cat can lose a significant amount of kidney function before looking sick in any obvious way. The early signs are subtle:
- Drinking more than usual, or spending more time at the water bowl
- Larger or more frequent litter clumps — the earliest and often most noticeable at-home sign, since failing kidneys can't concentrate urine the way healthy ones do
- Gradual weight loss, sometimes even while your cat seems to be eating normally
- A duller coat, or grooming less than usual
None of these are things to panic over individually — but if your sitter knows your cat's normal water and litter pattern, they're in a position to notice a change worth mentioning to you, rather than nothing standing out because they have no baseline to compare against.
Arthritis: often missed because cats don't limp
Most cats over ten have some degree of arthritis, but they rarely show it the way dogs do. Watch for:
- Hesitating before jumping onto a favourite spot, or avoiding jumps altogether
- Difficulty getting in and out of the litter box, especially a high-sided one
- Reduced grooming, sometimes showing up as matted fur around the back or hips they can no longer comfortably reach
- Increased irritability when handled, particularly around the hips or spine
If your cat has any of this already, mention it — a sitter who knows "she's a bit stiff getting into the box, that's normal for her" won't mistake it for a new problem, and a sitter who doesn't know will have no way to tell the difference between ongoing and new.
What to actually set up for a senior cat
- A low-sided litter box, or an additional one somewhere easier to access, if stairs or a high-sided box are a struggle
- Litter box placement on every floor, if your home has more than one level — this matters more for a senior cat than it did when they were younger
- Any prescription diet, and why it matters — some senior-specific diets are part of managing an existing condition, not a preference, so substituting "just this once" isn't a neutral choice
What's manageable versus what's worth a call
Generally fine to monitor, not panic over:
- Slightly increased thirst or urination that's consistent with what you already know about your cat
- Some stiffness or reduced jumping that matches their known baseline
Worth a call to you or the vet:
- A clear increase in drinking, urination, or litter clump size compared to what's normal for your cat
- Weight loss you can see or feel, especially if appetite seems normal
- Vomiting, noticeably reduced appetite, or lethargy alongside any of the above
- Any sudden, sharp change rather than the gradual pattern that fits ongoing ageing
What to actually hand over
- Your cat's normal water intake and litter habits, as a baseline to compare against
- Any existing diagnosis — kidney disease, arthritis, or otherwise — and the current management plan
- Prescription diet details, and why substituting isn't appropriate even briefly
- The specific point at which you'd want a call, since "seems a bit off" means little without a baseline
Why this belongs in the handover, not just your vet's file
A vet sees your cat once or twice a year. A sitter, over a multi-day stay, can actually notice day-to-day changes — but only if they know what they're comparing against. Without a stated baseline, subtle warning signs just look like "an old cat being an old cat."
Quirks & All keeps your cat's current baseline and any diagnosed conditions on their profile, updated as things change, so a sitter has an actual comparison point rather than guessing at what's normal.