My child has nightmares -- how do I help?

Comfort. Childhood nightmares are common occurrences. They are not dangerous to the child and do not predict anything about future development. However, they are scary to the child and can make bedtime difficult. During a nightmare, go in and comfort your child. If they are awake talk about it and show them it was not real. Sometimes having a nightlight in their room helps. Read stories before bed.
Comfort and calm. When your child has nightmares comfort them and calm them first. Then ask them what it was about and educate them that you are always there and will keep them safe. Don't draw the time out but calm them and move on to getting back to sleep.