Hi... My 17 month old has been a good sleeper since we did controlled crying (2 nights) at 10 months (she was waking every hour since 6 months). She has a good routine. In bed at 7/7:15 and sleeps (mostly through the night) until about 6am (+/- 30 minutes). Then she has a nap between 12 and 1 for 1.5 hours. she's been refusing naps on more and more days recently. She's way too young to drop a nap. Any recommendations of what it could be?