if your yorkie has tear stain problems, apple cider vinegar might also help.
"You could continually wash away your dog's tear stains, but that affects only the result not the cause. Putting
a teaspoon of natural apple cider vinegar per quart of water in your dog's water bowl can clear up most active yeast infections and prevent future infections. Apple cider vinegar tablets can be used if your dog refuses to drink the treated water. A dog's (and human's) system should be PH balanced (between acid and alkaline), and apple cider vinegar adds the acid that many of us are lacking."