This is a good example of a "before and after" shot. In the first photo, his left eye is shown as he would normally have it. In the second photo, he's been asked to open his left eye. (He's the blonder boy on the right side of the photo.)

I'm just adding some recent photos. You can see that his eyes are not always symmetrical. He can open his left eye to better match his right eye, but only does so when reminded.