Glory
There's nothing quite like taking away the pain of a child. Most doctors enter into the medical profession with glory at least a little bit on their minds, and really, why shouldn't they? Medicine is a noble profession and they've worked hard to earn a place in the field.
While doctors' intentions may be generally pure and come from a good place, they also want to be admired, looked up to, and relied upon. As a pediatrician, your patients will literally look up to you. It's a nice bonus.