Treating Kittens with Eye Discharge?

I recently had a momma kitty give birth to a litter of 5. She had them outside and it took me a couple days to find them. I finally found them and had found that one of them had died. I brought them inside and I am not completely sure if it was the first night or the next, but another one had died while inside. They are a little over 3 weeks old now and there are now 3 of them. One of them had one single crusty eye and now that it's been a few days all three have at least one crusty eye. The original crusty eyed kitten has both eyes crusted shut and the other two kittens just have one eye crusted shut. I don't have the money to bring all or even one kitten into the vet right now so I was hoping someone could let me know of inexpensive medicine or at home remedies to help. Thank you in advance.