How do they have the development to learn these subtle lessons?
This is a karmic lesson from a past life, either for something they have done, or to learn what disease teaches, which is to treat the body as a temple. A sick child may have (in a previous or several past lives) abused their body physically. This lesson (as many are) is also tied to others and their lessons. Parents who have a sick child are forced to their heart center and learn the importance of love and compassion. In this way we are all connected in healing.
