Nightmares occur later in the night during REM sleep and involve vivid images that will often be remembered in the morning. They are not generally considered a form of sleeping disorder unless they seriously affect you. As they take place during REM sleep, you are more likely to remember the nightmare and if it is your child that is suffering from the nightmare then you should try not to fuss or bring up the nightmare in the morning. As they can be quite distressing and disruptive, then nightmares can become a problem, especially recurring ones. It is thought that nightmares stem from a problem that our mind is trying to solve but cannot, and often the nightmare will not represent the issue in hand. If you do suffer from a recurring nightmare, then the stress that your mind is trying to solve is evidently still present in your life. It is thought that if you think about this nightmare during the day and think how you would change it if you could, it can help solve and even get rid of this nightmare.