Stellaluna by Janell Cannon, Jewell Cannon
Stellaluna, a little brown bat, is accidentally dropped by her mother. The helpless baby falls smack into a nest of fledglings and is immediately accepted as one of the family. Stellaluna tries to fit in but keeps acting unbirdlike, hanging upside down and wanting to fly at night. By chance Stellaluna is reunited with her mother and finally learns to be a proper bat.