I think you pretty much answered your own question with how to prevent it with the next child...not rocking him to sleep. :) The rocking has become a crutch to your child's sleep it sounds like. He doesn't know how to fall asleep without the rocking, so when he wakes up in the night (as all children do I hear), he cannot fall asleep again without the rocking (whereas other children would fall back to sleep on their own without anyone else ever knowing they woke). Though the rocking is so comforting and precious, it has become a burden. I too also recommend the Healthy sleep habits, Happy child book. It's been a while since I read it (like 3 years), but I remember it having a lot of great input. To train him again to fall asleep on his own, I would try to gradually lessen what you do for him in the middle of the night, whether it's shortening the time you hold him, to maybe rubbing his back instead of holding him, to standing next to his crib and just being there, to standing by the door, to standing just out of sight...whatever it takes to progress. There may be some tears, but whatever you can do to progress him to learn to fall asleep without the crutch of needing someone to hold him will help for restful sleep for him as well as you. With preventing it for the next too, a schedule/routine really helps to know when they are tired. My kids didn't LOOK tired when I laid them down, though I knew when they were tired and they would go right to sleep for their full nap or through the night, whatever it might be. Oftentimes when you wait til they show signs of being tired, that's when they are getting OVERtired and it actually gets HARDER for them to fall asleep. Gotta ideally catch them when they are tired, but not too tired, which is why the schedule/routine helps SOO much. Routines helps so much with healthy restful sleep. Helps them to take full meals helping them to take full naps (1.5-3 hours depending on age) instead of the cat naps that don't allow them that REM sleep. And go ahead and cuddle and rock your babies, but just do so while they are awake, so they don't DEPEND on it for sleep. Best wishes to you and enjoy your precious little ones!!