Even life threatening diseases, such as leukemia, do not affect children the way they affect adults. Disease means much more to adults than to children. By the time we reach adulthood we have learned to value illness. Part of the loss of our childhood innocence involves the knowledge of dis-ease. Separated from our childhood ease, we discover the world of personal struggle.
Illness stops being just another experience to go through.
It takes on an ego value, and becomes something to use and benefit from. I remember breaking my elbow at the age of five. It hurt and I screamed. In a few minutes the pain had mostly gone away, at least it was not so great that I needed to scream. I looked at the entire family around me, relating to me because of my pain and misery.