Your situation is actually extremely different.
OP is trying to get a non-minor sister included as a dependent in a parent sponsorship application. You have a minor child and are concerned about them passing the medical. These are two completely different scenarios.
The outcomes of this case won't in any way be relevant to your situation.
For your situation, your son should be able to pass the medical however may be asked to complete additional medicals / testing depending on how the first medical goes. However his situation should not prevent you from successfully applying.
