oh! I know this one! shadow has the same problem, the tear ducts under her eyes are clogged, its not something you can fix, but it causes a lot of tears to run down their face, shadow is a sheltie mix, and tear stains are not commen for her breed, she always has the stuff running all down her face, and sometimes it turns the colours she described the best tear stain removal I can recommend is baking soda and a little water, just put some of this on an old toothbrush, and it scrubbs the stain right off, much better then any commercial stain remover