Children know how to recover from past stressful experiences. They do this partly through their play. You can encourage your son to re-enact through play past frightening experiences, such as doctor visits, saying goodbye to grandparents, or moving to a new home. For example, you can give him a doctor kit and suggest that he play doctor with you. He will probably find ways to use the materials and your attention to create meaningful, therapeutic play that will help him work through some of the frightening or painful experiences he has had with doctors and illnesses.
Children also use tears and tantrums to heal themselves from stress and trauma.
It is important to allow your son to express himself in these ways, even though his emotional outbursts might seem to be out of proportion to the events that trigger them. If you can stay close and listen lovingly when he cries or rages, you will be helping him to recover from whatever past hurts he has experienced. This can be done without punishment. Simply step in as needed, hold him firmly, and explain why you must prevent him from doing what he is doing. Setting limits in this way often triggers a healthy release of tears in the child, and this will be very beneficial for him.