Hello It seems from the history that your grandson is having poor vision in one eye. First thing to be done is evaluation of the affected eye to find out the cause for low vision in that eye. The common causes are refractive error or congenital problems like cataract... Ambylopia is seen when two eyes have different vision leading to underdevelopment of the eye with low vision. Ambylopia in this age can be effectively treated by using occlusion therapy after correction of the underlying problem if any in the affected eye. Hence no need to worry do consult your pediatric ophthalmologist for examination and treatment accordingly. Thank you