Is it possible for a 6 year old girl (diagnosed with OCD) with no previous knowledge/ exposure to sex, to have obsessive thoughts related to sex?

 

This is coming from a Psychology Student:

According to Sigmund Freud, the Father of Modern Psychology, our brain is like an iceberg. The visible part of it consists of the conscious and the preconscious part of the brain, whereas the part which is inside, is the unconscious part. He talks about Id, ego and superego, where Id is a part of the unconscious, where all the innate drives dwell. Sex is one of these drives. Human beings are programmed to seek pleasure or as he said, immediate gratification. They are innately impulsive and seek pleasure one way or the other. Age 6 comes under the phallic stage, one of the stages described by Freud in his Psychoanalytic Theory. At this stage, the child realises the difference between the two sexes and becomes aware of sexuality (Read about Oedipus complex)

Oedipus complex - Wikipedia

The sexual desires, (though the kid does not know what sex is) get repressed due to the fear of punishment (Read about castration anxiety)

Castration anxiety - Wikipedia

The question arises, where do these sexual desires come from?

Like I mentioned, according to Freud, human beings are born with genetically programmed impulses (sex, aggression, etc)

The intrusive OCD thoughts of your kid might not be vivid. But the kid sure has an idea. She is unconsciously aware of it, and though she never thinks about it, the images pop inside her head. This is a very stressful condition. Tell your kid not to feel guilty about it. Feeling guilty will make it worse. Tell her that there is nothing wrong with her, she doesn't have to take responsibility of these thoughts. And whenever she gets them, she should tell a parent about it. If possible, take her to a CBT (cognitive behaviour therapy) expert

Good luck.