Somewhere between 12 and 24 months of age, your toddler will likely resist a morning nap and want to rest only in the afternoon. Your child's attempt to switch to one nap a day often occurs at about 18 months of age. Many doctors recommend keeping both naps as long as possible for both the child and parents' benefit.
When your child transitions out of a morning nap, you can try blocking out time in the afternoon for a quiet period. Even if your child doesn't sleep, he or she usually still needs a restful break.
A toddler's excitement about learning to walk and emerging independence can sometimes also disrupt afternoon nap schedules. Toddlers often are more eager to practice new skills than to sleep. You may want to try some of the following strategies to help your child get needed rest:
WebMD Medical Reference from Healthwise