My 5.5 month son is a pretty good sleeper at night time, but struggles to take solid naps during the day. We have worked our way to a 4 hour EASY, however we are plagued with short naps; sometimes only 45mins, maybe an hour, and on a few occasions 1.5hrs. I use the wake to sleep method to disrupt him enough to extend his naps, but end up having to do it multiple times per nap....to get over the transitions. If he does wake early (45min-1hr), he's always in good spirits kicking and chatting away in his crib. I need to use pu/pd to nip the short naps, but I'm wondering when it is appropriate to enter his room and begin? Since he's happy upon waking...how long do I let him play in his crib before beginning pu/pd? Do I wait until he cries (which may be an hour)? I would like him the go back to sleep on his own....he did this once after playing for 10mins...but it's unlikely to happen. If he naps for 1.5 hrs.....should I be satisified with that or does he need to have the full 2 hours nap? How do I proceed?