My friend's 4 month old DS has learned how to roll and at night will roll from his back to his front in his sleep and can't get back over (he can sometimes get from front to back during the day - I think it's that he doesn't have room in his cot or it might be because he's in a sleeping bag) - then he will wake up and cry because he wants to be turned over. He did it every 2 hours last night which is taking its toll on them all.
Do you think it would be safe to use a sleep positioner or something to stop him rolling in the first place? She doesn't want to co sleep as she tried it but was too easily disturbed by his wriggling and feels her bed is too small.