My seven year old german shepherd started showing signs of urinary incontinence when she was about 5. It can happen to some spayed females, it's like weak bladder muscles. She will not do it on a hard floor, I don't know why, and it's only when she's sleeping. She did get better on a widely used medication called PPA. There is also another drug, I believe a steroid, called DES if the situation is unbearable and PPA dosen't work. However, as like all steroids, it will deteriorate the organs over time. We weighed the options as PPA didn't help completely, but decided her health was more important than a few spots on the rug. We tiled the main part of the house and she has her own rug to sleep on in the bedrooms.