I would have a vet visit. He or she may have an infection and it can be dangerous if untreated. Not to be ignorant, but can you smell the urine? If it has a really strong odor he or she(one in a while) could be spraying instead of urinating. This is much harder to stop than regular urinating. I had a female who would back up to a door and spray. We finally took that door out of our house and replaced it. She constantly had infections no matter what we did for her, which caused the spraying to begin. I also used some of the cleaners from Petsmart to neutralize the odor.