My baby will be 6 months old in a few days and I have been working on her eat,play, sleep routine since she was about 4 months. It seemed to be going pretty well except recently she will only nap for 30 mins. So basically she is waking up after he first sleep cycle and can't go back to sleep on her own.  I've tried shushing her, patting her, nothing works except physically picking her up and rocking her.  She does sleep all night so that's our only saving grace right now. Any tips to get her to nap longer?