DD had become rubbish at sleeping at 9 m - waking almost every 2 hours. I was feeding/rocking back to sleep and was knackered.
Then I noticed (by co-sleeping out of knackeredness) that what seemed to be waking her was farting! I posted on here about it, and was advised not to feed her veg with her evening meal. I tried this and instantly she slept through! Seems too much of a coincidence not to have been the answer.
So - if you are in the same situation I advise you to try it - I feel like a different person!