However in your son’s case the symptoms are far apart, except for the rash
and fever. These are also signs of meningitis, but that is a more serious condition
and will not linger for so long without serious repercussions. Diabetes should definitely be looked into. Rocky Mountain spotted fever is another possibility. Refractive errors of the eye should also be looked into. Fungal infections too should be investigated.
Hope this helps. Do discuss these possibilities with your son’s pediatrician.