Childhood sexual abuse is a silent crime; the perpetrators will not speak of it and their victims cannot speak out.
The majority of perpetrators know their victims: in many cases the victim is in their care.
The crime is often cloaked in terms of affection and secrecy.
Where the abuser is a parent, the child is trapped between the need to seek redress and the ensuing effect upon the family. often the victim remains silent, but her behaviour will indicate her suffering. This makes the extent of the crime difficult to quantify.