My DS is just over 6 months now, and has recently shown me that he can put himself to sleep for his naps, and if he wakes during the night(usually early am) However, when it is nap time, since he is on the 4 hour easy he would be "sched" to sleep around 9:30 or so..so I place him in his crib around 9:15 so he can play, and then drift off. Today for instance, it took 45 minutes for him to fall asleep, and that was because I had to go in and pat/shh him to sleep. He was clearly tired..but if he is not falling asleep within a certain amount of time 15-20 min? Should I be going in to assist him?