Miffy seems to be urinating on herself. I've picked her up a few times and her belly area is moist and yellow. She also smelled like pee. (I gave her a bath.) She's eating, drinking, active. I feel she may have started losing weight, just a little. She is about two years old, and my first instinct is that she's just showing her age. Sprinkles had the same problems as she moved on in her life. Has anyone experienced this before?