How can I tell if my child is having a nightmare or a night terror?

If children are waking with night terrors, they're probably not night terrors. If they actually wake up, that's generally thought of as a nightmare. During a night terror, children will still be asleep, but they'll be frantic and screaming. If they are still asleep, then don't wake them up, because that can really startle them -- they won't remember what it was they were screaming about if it's a night terror. With nightmares, they will wake up and they'll remember the dream. That's the difference between the two.