I agree Jo, in that it does sounds like a night terror, but these *usually* happen in the early stages of sleep - it's not normal for night terrors to occur so late into the night. However, the stretching thing and screaming is exactly what DS does when he's having a night terror.
If it is a night terror then, as Jo says, unfortunately there's nothing really that you can do, other then try to find the cause. It's ALWAYS down to OT with DS. Always.
What sort of routine is she currently on?
(Oh, and welcome to the site!
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