I bet he is partially blind. Like he can see from a certain angle only... cause it happened to my older sister. She can somehow still see but only if the light enters her eye when she lifts her head up. She's blind on the right side only. It's a rare case. Not sure what the condition is called. My sister is very sensitive about it, and she won't say much about it. Although she is the type of girl who told us her daily activities or what her classmates do every day.