DS started sleeping through (7-6) at 7.5 months but within a few weeks started waking at 4.30/5. This coincided with teething, early mornings and a lot of physical development (crawling etc.) He's nearly ten months now. It doesn't seem to be about hunger and if I feed him and take him into my bed, he gets excited and smacks me in the face repeatedly until I give in and get up. We put up blackout blinds a couple of weeks ago and that has made some difference - but only until 5.30 (I know, I know, I'm lucky that he sleeps through at all...)
A couple of people have said that if I cut down or even stopped his morning nap it might help (I don't think he can go until lunchtime without a nap). He currently goes back to bed at 8.30/45 and sleeps for up to 1.5 hours (and the same again or longer after lunch).
Has this worked for anyone? I currently try and nap when he does and so am loathe to cut down on my his sleep if it's pointless.