L.C.
A. -
My husband has spent over 20 years in the field of sleep. Dealing with disorders and such, I asked him about this and he had the same problem until he was about 10 or 11. It is more common in boys but he says this is completely normal. She will outgrow it. With him, it had to take something new to get him to stop, for example, his parents got him a new bed and told him it was a 'special' bed, from one day to the next he stopped.