Hi. I'm online and happy to answer your question today.
The spots on his eyeball may areas of thin sclera (the white wall of the eye) that is allowing the inside of the eye (uvea, which is the retina, choroid etc) to show through.
Here is a nice article that talks about the parts of the eyeball:
These spots might mean that your son is nearsighted or, most likely, it is nothing to worry about and it just the way his eye is.
I agree with the plan to have him examined and suggest you take him to a pediatric ophthalmologist. They are the best trained physicians to do a complete exam on a child. As far as the spot at the base of his spine I do not think this is related to the eye findings. What does your Grandson's pediatrician think about this spot on the skin over his spine?
Does this make sense to you?
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