Try washing the kitten's eyes with a warm saline solution. I think you use 1 teaspoon of salt to 1 quart of warm water
Good luck! You are a kind soul for taking care of these needy babies and mommy.
In our organization there is an organization called Sterile Feral. It has a capture-release program. They will capture will domestic cats spay/neuter them and release them back to the same location where they were captured. The stipulation is that the cats must have a mentor who will feed them. Before release the cats are wormed, given 3 year rabies vaccines, feline lukemia vaccination and whatever else it is that cats need.
I have four in my barn that I "adopted". They are semi-wild. They do thier job well -- keep the yucko plucko mice away AND the huge bonus is that they don't want to be touched.
I am not a huge fan of cats