My sister was diagnosed with Obsessive-compulsive disorder always needing to perform rituals. Are you familiar with OCD?
I do not have a lot of knowledge about it.  I frequently read that more and more children are being diagnosed with it.
My sister started exhibiting some of the behaviors as a child always needing to wash her hands or turn a light off 3 times. She says that she is unable to control theses thoughts until she does the ritual.
What an affliction.  Do doctor's know what causes it?
The cause is unknown by there seems to be a genetic component.
Do your sister's conditions change much, or is she doing the same things since she was first diagnosed?
She has undergone cognitive behavior therapy and it has helped reduce the hand-washing ritual at least to the point she no longer has raw skin or bleeds.
It is great that the treatment seems to be working.