Please have your dog's urine checked by urinalysis to determine if your dog has a urinary tract infection or diabetes. Other common causes of inappropriate urination include: kidney disease, Cushing's syndrome and other hormonal disorders, urinary incontinence, cognitive dysfunction, or behavioral disorder.
Hi there..
First, I want you to be aware, that I am not the vet...but I noticed your post, and would like to tell you that I had a 15 year old yorkie...she started peeing in the house..and wanted to get out at night more often...also drank more water....I brought her in for a check up..I thought she might have had a urinary infection. The vet did blood work, and discovered it was kidney disease. Please, get your yorkie to the vet, and have them do some blood work. Any dog that is 13 should have blood work done to help assess their liver and kidney functions.
Best Wishes to you and your dog....
Connie