Whether it’s Darth Vader, the Daleks in Doctor Who or the winged monkeys in The Wizard of Oz, most of us remember seeing something on screen that we could only watch from behind a couch or under one of our parents’ coats: in fact, 90 per cent of adults report an enduring memory of having been traumatized as a child by something they saw on television or in a movie. What we may not remember, however, is how serious and persistent the effects of these frightening moments and images can be. As we guide our children through their media experiences, it’s important to realize that what they see can lead to problems like vivid nightmares, fear of the dark, having trouble sleeping and refusing to sleep alone.