 some type of problem, we'll just say they're farsighted, where they see fine far off. And so they look normal on the playground or interacting with their friends, but yet when they go to read or look at a digital device, it's uncomfortable. And the child doesn't know to complain because they don't know what their vision is supposed to be. But yet they have this aversion to learning because every time they try to read or study, their eyes bother them.