It's my understanding that if the child remembers what happened in the morning, then it is by definition, not a night terror.
My son is also very hard to stir. I turn on the lights and take off the covers. If I still can't wake him, I will put a cold washcloth on his forehead. It sounds cruel but it's not as cruel as the 30 min terror that comes an hour later if I don't.
I have heard that sleepwalking and other sleep issues are hereditary but not night terrors. They seem to occur in early childhood and be triggered by a disruption in schedule or stress. At least that's what everything I've found says.
