My 3 year old girl isn't sleeping good at night. what could be wrong. and she don't nap.

Night time routine?: If this is a new problem, she may be uncomfortable. Ear pain can get worse at night, for example. How is she acting when she wakes? Does she seem comfortable but just wanting to play? Is she in pain? For any concerns such as these she may need to see her pediatrician. If this is not new and she just wants to play, there are measures you can take to help her sleep. http://www.mayoclinic.org/healthy-living/childrens-health/in-depth/child-sleep/art-20044338?pg=1