Crying in his sleep?

Spencer was just really crying I went in to him but he seemed to be asleep and had stopped crying by the time I got there (which took about 2 secs). Have just heard it happen again over the baby monitor, not sure if he was asleep but he let out one cry and then it when quiet again. I think it has maybe happened before but the nursery door was quite noisy (has just been oiled) so that could have woken him up when I went into check as he would be very drowsy and kind of out of it looking.

Any ideas?

I've heard him chatting/snuffling in the night so do normally give him a few minutes but this was a real cry and he doesn't cry very much.

Sam does this too. It used to give me a real fright when she did it, but as the others have said it is normal and atleast he is self settling.

We have also had the odd occasion after Sam has gotten really upset that she will sob in her sleep for ages afterwards

Sometimes I wonder if it happens when there is a small niggle annoying them such as teething or a cold or something. They are asleep but semi-aware of the irritation so they cry a little. They probably don't remember it.

edited to add 's'

Edited by FionaS

Cooper does it too, sometimes it can be quite a wah wah cry and you go in and check on him and he's fine and has gone back to sleep... he does it during the day too. Sometimes he gets to a point where you have to pick him up..but he'll fall straight back to sleep after you've given him a cuddle...

Gina has done it too. Not very often so I always go into her room to check up on her.
I second what Fiona said, I think Gina has only done when she's had a cold or teething so must be still aware of being uncomfortable. Poor wee bubbas