Missy it can be environmental. Right now three of mine are having AWFUL tearing when they never tear otherwise. The only thing I can think is that they have some kind of cold or are having some kind of allergy to something. I dry their eyes 3-5 times a day. I do use Angel's Eyes when they start to tear excessively, at half dose, every other day. That seems to really help. I don't recommend long term usage of Angel's Eyes but 2-3 times a year for 1-2 weeks is not going to hurt them. I find that having them on a supplement along with raw such as Nupro or Missing Link reduces tearing. I do not now why. I also find that giving bottled water over tap water greatly reduces staining. Both of yours have masks over their eyes, are they tearing below their masks?