Hi, I'm Dr. Deb. I will do my best to assist you today.
Constipation is a fairly common problem as cats age but it's important to rule any underlying disease process such as kidney disease and dehydration.
Has Kitkat had any recent blood work done?
Older cats lose anal muscle tone which makes it more difficult for them to defecate, they can also develop a little arthritis so it is more uncomfortable for them to "assume the position" so to speak for long periods of time.
Increasing her water intake is important and one way to do this is to feed her wet/canned food, if you're not already. Using daily laxatives, such as laxatone, laxaire (there are many different options available from either your veterinarian or the pet store) can often soften the stool enough so that it comes out easier.
And, if those options don't work, you can give her a little Miralax (the same product we take) mixed in with her wet food.
If she is a long-haired cat and grooms herself a lot, hair can cause the stools to be really firm so that brushing her every day can help reduce the amount that she ingests. The laxative I mentioned work really well for this problem too. Even if she is starting to have some trouble with her kidneys, these options are reasonable. I would just want to know if this is the primary underlying cause.
I'm not sure if you're online or not but I hope this has been helpful and answers your question. If you would like to chat about it more, please let me know.
This website may also offer some additional insights into this problem although it discusses the problem in dogs as well as cats:
What you suggest is what I was looking for. She is a short hair and does not cough up hair balls, so she often has hair in her stool. She has always had dry stools.
I would definitely have some blood work done.
...just in case but mostly because of her age.