L.M.
What does he do when he wakes? Play quietly on his own - let him be. If he lets out a mantra cry (deliberate wa wa cry like whining) Option 1: leave him for a while. The amount of time he spends crying should decrease each night (this most likely means he is waking out of habit and just wants you to come in.) Option 2: go in and lay him down and let him know it is time to sleep. If he stands back up, lay him back down (talk or pat his back to sleep. This will take a while to begin with but take less and less time each night. Interact as little as possible and try not to make eye contact (don't want to make it fun). If he is waking at the same time every night (say 3am), go in 30 minutes before the waking (2:30 for example) and stir him a bit. Often a habitual waking like this is because they are not able to transition well from one stage of sleep to the next. By stirring them (but not waking them) you are resetting the sleep cycle and they normally won't wake. Do this for three nights and then the waking should stop.