13 Year old Havanese who sleeps in our hallway at top of steps. He has the run of the house and in the last year or so he will go down into our living room and pee on the floor. We had carpet in the room and since removed to be replaced by hardwood floors. He will go outside right before bed each night. Even in the last the two days I will go downstairs and see a pee stain right in the middle of the floor. I took him to a vet about six months ago to be evaluated. Fecal exam, blood collection, basic profile, urinalysis and cystocentesis tests done. All showed normal. He was given antibiotics for 10 days and seemed fine. Pretty frustrated and not sure what to do at this point?