Remember that in caring for a sick child you are also caring for the family members, as well. Parents can either be wonderful or the parents from h***.
And there is not always a happy medium.
So in addition to being the nurse and being able to help the child, or at least trying to, you are also functioning as a little bit of everything else, such as psych (even though they may be seeing someone already) specialist, social worker when they aren't available, etc., etc.
Hope that his helps...........if I think of anything else I will post it in a few minutes.