Unusual Bird: “Crazy Eye” male northern cardinal

My sons (ages 6 and 8) first noticed this unusual male northern cardinal at one of our feeders back in February. At that time, the cardinal still had most of his head feathers, and the most striking characteristic was the pronounced white ring around his black eye. It was especially striking in contrast to other cardinals, whose black eyes blend in perfectly with their black face masks. My sons affectionately nicknamed this bird “Crazy Eye.” We have been seeing him at our feeders several times a week, but it has been very hard for me to get a picture of him until today, as he is extremely skittish (more so than the other cardinals at the feeders). I lucked out today and was able to get few pictures through the window. As is visible in the pictures, this bird has lost most of his head feathers over the last two months. He does not act injured or ill; the only behavioral difference I can see from other cardinals is its skittishness.