Psi-man Heal My Child!
"Psi-man Heal My Child!" is a short story written by Philip K. Dick in 1955. It also has the alternate titles Psi-man and Outside Consultant and appeared in Dick's short story collection Second Variety.
The story revolves around a group of 'Talents', who are people with varying psychoactive powers in a post-apocalyptic setting. The remaining survivors of humanity are hunkered down in isolated communities and can only leave with permission from their military leaders. The main plot of the story is of a family who chooses to have a Talent heal their daughter of cancer instead of the harsh treatments of their local hospital. A side plot involves one of the Talents, who has the power to traverse time, repeatedly attempting to change the present by returning to the past.