My friend recently told me, that when we had sleep overs, in the middle of the night I would often sit completely up right and say something then fall back down. She said most of the time it was something like her name or hi, but there where I few times where I terrified her. She said on our first sleep over I said "Wait for the sun to rise again." And on our last sleepover I actually got a huge smile on my face and opened my eyes and moved my hands saying tick tock faster and faster before falling back down. She said she had tried to wake me up before and nothing had happened, and that I was fast asleep. I have no recollection of this and was honestly shocked when she told me this was happening. Does anyone have any insight?
I'd ask a doctor before anything else. Sleep disorders can cause things like this (including doing things with one's eyes open). Some people even prepare food or drive in their sleep, so sitting up and talking isn't out of the question. Sleep disorders are treatable, though, so if that's what's going on there are measures you can take.