Sorry about getting back to you so late but I have been to a veterinary conference and have just returned. It is really nice that you care about these strays!
The mother cat with the scabs and pimple-like lesions on her chin may have feline acne. There is nothing that is safe to do for the pimples right now while she is nursing since almost any medication that you can give her internally such as an antibiotic, or even topically is too dangerous to her kittens. As long as she is happy, and eating and drinking I would not worry about the problem until her kittens are weaned. Than you can use a topical ointment daily such as benzyl peroxide cream on the lesions after scrubbing then rinsing the lesions with a anti-bacterial soap (if the cat will allow you to).
The same information goes for the other mother cat with a sore on the side of her face. She really cannot be treated until she has finished nursing. Her problem may be more serious. It could be a bite wound abscess, or other sore that is healing, or cancer or other problem. When you bring her in for spaying maybe it can be examined and treated.
Cats in colonies commonly have herpes and other infections. Herpes causes upper respiratory infections such as runny eyes. A Herpes infection can go away on it's own, than will lie dormant for a period of time, but will return at a later date when the cat is physically or emotionally stressed. There is no cure, but it can be debilitating, but very rarely serious unless complicated by feline leukemia, AIDS, or FIP.
I would contact the Humane Society and let them know of the situation as quickly as possible. Often, if the cats and kittens are deemed suitable for adoption, they will spay them, vaccinate them, and nurse them back to health if they do have problems.
And then the cats won't have to be strays anymore. They will have homes.
Please do this. Stray cats do not have an easy life, and die young from disease, injury, or starvation. If unspayed, they produce more strays who lead similarly miserable lives.
Unfortunately we don't have Humane Society here. Because I live in Turkey. I have to have spayed month later. These mother's are nursing them. Also, those two mothers won't come towards me that much. Let's see what Dr. Cheng says here, but thanks for your reply.
Ah. Its hard when there is no location listed on your profile. I hope Dr. Cheng can help.
I believe the mother cat with skin problem have scabs. Don't know how to clean that with.
It seems the cats are doing ok. Now there is another cat with watery eyes. No runny nose, no mucus or color. Its a tabby cat. Can I give the cat something or will it go away on its own?