Yes, that is why when they are having clear symptoms of the risk disease, they go to their doctor expecting him to determine what is wrong. If a medication-caused illness is “rare” that does not excuse the medical profession from properly diagnosing and treating it, especially now when diagnostics is fairly easy, in a case like this one. Criminal medical negligence. It’s ridiculous to blame the poor child victim.
Diagnostics is far from a precise art. There are many cases where a set of symptoms fits many diseases/causations.