Our son has had night terrors since he was about 12/18 months old. He had them frequently for about a year then they tappered off. I never related it to staying up too late; but now that you mention that possibility; it makes a lot sense, considering our life then. He is 3 1/2 now and still has them occassionally. He even has them in the car. If he fell asleep in the car seat and he woke up in the car, or if he'd fallen asleep by the time we'd get somewhere, when we would go to take him out of the care seat; he would have them. Most times they were really severe and scary for us. We used to be on the road a lot, 3-6 hour trips; we would have to stop somewhere; take him out of the car, hold him very lovingly, walk around with him and talk to him...in the cold months that seemed to help him more than the warmer months. It seemed like the cold air outside helped snap him out of it; once he'd calm down enough, we would let him walk it out himself (holding his hand of course, as we were usually at rest stops). Breastmilk was his primary source of nutrition for first year; he still nurses occassionally (at bedtime), but nursing him usually helped calm him quite a bit. Somtimes his terror episodes would last 45 minutes to an hour; sometimes it seemed like nothing we did would help. He too would throw himself around; jerk his body kind of violetnly, and sometimes he would take both his hands and dig into his face and run his finger nails down his cheeks actually leaving long red streaks on his face. My husband was a long haul night time truck driver then, and we were all on a very irregular schedule; our sleep patterns were often almost opposite of everyone else we knew. But since you mentioned it; I am now thinking lack of proper sleep and regularity might have been a huge contributor. In the past year or so, my husband has been out of a truck and both us have been working regular day-time hours and our son has been in preschool...we have a much more structured schedule and he has had very few of the night terrors. We were all up later than usual last night (we had a great evening together), but it was a late evening and about 2 hours or so after he went to sleep; he had a night terror. One thing I have noticed also is the change in them; now they are more like emotional episodes rather than resemble weird temper tantrums. Now he stills jerks his body a bit, but he will have very emotional tearful episodes. I know I have now rambled on....but I read somewhere and our pediatrician had also told us ...that there was nothing we could do, but to let him work it out himself; that if we tried to stop these terrors while he was having them, that we would make them worse. We found that not to be totally true for us. We just try to comfort him securely with coddling, talking softly to him, or stepping outside with him, or find something that fascinated him, and try to get his attention on it. For example: he loves BIG TRUCKS, so when we were on the road and had to stop, getting his attention on all the big trucks at the rest stops up close helped frequently. When at home in middle of night; I still usually nurse him or cuddle him in our bed, lightly rub his head or back and within a few minutes, he now falls back into a peaceful sleep. I hope this is somewhat helpful to you; you have actually made me aware of what I now think could be a primary cause of our sons terrors. I am thinking maybe they come from them just being so exhausted combined with irregular or out of the ordinary events. There have been a lot of things we have noticed have been much improved by our more structure life with our son, maybe this we can add to that list of reasons to keep him on regular structure schedule, as hard as that can be now a days. Good luck...and sweat dreams :).