My 3 year old kid enjoys looking at straight lines sideways and follows it. I hope he does it out of curiosity, and not a condition. Let me know if anyone else does it too.

A. A lot of kids like that they do different things at different time I’m very sure it is just a time pass kind of a thing with a child is exploring something new yet if you see the thing is happening happening continuously even after three or six months then you get a chat with your doctor