What are the tiny brown spots on my cat's eyes?

My 6 year old cat got a couple tiny brown spots on the bottom inner edge of his eyes. Now there are more and in both eyes. No medical issues. Her littermate sister had to be euthanized in December due to an extreme blood disorder that multiple Veterinarians thought was a complication due to cancer. It happened so quickly like a runaway train. No other littermates have had cancer. What are those spots?

It's impossible for us to know what they are, but they could be something called corneal sequestrum.  I would definitely take him in to be seen, preferably by a cat ophthalmologist (yes, there IS such a thing ).   You could try your regular Vet first, but I would probably CALL them and see if they think an ophthalmologist first would be best and save myself some money, since often in these cases, they get referred anyway.