My 7 year old DS has been a great sleeper for a long time now, his only prerequisite is his bedroom door being left open until he falls asleep.
Until the last week or so when he has suddenly started having all sorts of panic about going to bed/noises outside etc. They have been studying Lindow Man at school (early man topic) and I think that freaked him out a bit to start with. We also have a load of noise bloody foxes that shriek and yowl at night, but whereas he used to sleep through this and it didn't bother him, he now almost lies awake in a state waiting for the noise to start.
He has also suddenly become very clingy to OH, who is actually away this weekend until Sunday so that has been upsetting him too.
Does anyone have any experience of children this age suddenly getting night terrors? I'm having to sit in with him for ages to try and get him to go to sleep, and he hasn't been falling asleep till gone 10pm most nights this past week..he was in tears at school on Wednesday through sheer exhaustion 
Any advice, or is it just another of these lovely stages that children go through?
Just to add, he doesn't have any issues at school, has lots of friends and during the daytime is a happy boy. He is quite sensitive though, and this sleeping thing is really getting to him.