We also have a blind or partially blind BR hen. We got her and didnt notice at first. It takes her a couple times to peck at yogurt but she does pretty well. We will be keeping her for a long time. She is very quiet and docile.
Basically, she has very limited sight because of cataracts that she was born with. Over time she has adapted and can probably see better now than when she was born. She has started laying green eggs, and even gets them in the nest box. She lives with 2 silkies and a younger Welsummer, and is actually the boss of them. She's turned out to be a great chicken.