My cats eyes are half covered by inner eyelids?

I have a black cat with yellow eyes who I socialized. He lives in the garage with two other socialized cats. One of the socialized cats is chronically ill very old, and the two other cats share bedding with him.  The black cat is about 2 years old now.  I noticed his inner eyelids are showing. They make his eyes look very strange, and it makes him look sick. They appear in the inner corner of his eyes and run around the bottom of his eyes. They are brownish in color. They cover about half of his eyes. I don't know if they are called inner eyelids, but I hope you know what I am talking about. Is this an indication of an infection? Will he overcome it on his own? Thank you.

It is a sign of illness, and he needs to see a vet.  What is wrong with your chronically ill cat?

the chronicially ill cat is very old. He came to me skin and bones with a very bad upper respiratory infection. I took him to the vet, and they gave him medicine, it cleared up his infection but it came back so I keep him on the medication now. He is very arthritic, and I figure he's 14 or 15 years old. He coughs a lot.