My 6 years old daugther has forced her girlfriend to play naked and let be touched

[bibou644]

We just discovered that our youngest daughter who just turned 6 has forced her best friend, a sweet 6 year old girl, to play naked in her room.
We found this out through the girl's mother after a talk with her daughter. Apparently our daughter threatened her friend that she would never invite her again, if she did not play naked on the bed and let herself be touched.
We don't really know how long this behavior has gone on and only know of that occurrence. She does not have many good friends and that girl is really the only one that has come to the house regularly. She is always tagging along with her older sister and her friends.
Her older sister is 8. They are taking bath together and never demonstrated any curiosity in that respect even when they don't know my wife or I are watching. Therefore I am a little doubtful that curiosity has anything to do with it.
My wife and I have had marriage trouble for the last 3 years and we decided to try separation a month ago (I moved to a nearby apartment complex).
What we have found though is our daughter has changed to a more aggressive/dominant playmate since she started public school last fall. Could it be a sign of a larger problem? Could my wife and I breaking up cause these types of behaviors? Are they to be expected from a 6 years old especially with another child of the same age and sex?
We plan on going to a child psychologist but what would you recommend? What is the best way to get a referal to a good doctor?

Please help.

[2terrified]

I'm sorry but there are ways to wash your hair in a tub without lying down to do it.  I was raised to use cups or buckets to rinse or wash in the tub.  

The important thing is where did she learn this from?  A child doesn't just come up with threatening another to lay naked and be touched in that way.  I know children get curious and play "doctor" or "house" but what bothers me is that the 6 year old threatened her friend.  I was sexually molested as a little girl and from what I remember, I didn't know anything about touching another person in that way until after that happened.  And my earliest memory goes back to my 5th birthday.  I was about 7 or 8 when i was molested.

[RockRose]

bibou644, how long was your daughter left unsupervised with this girl,  in a closed bedroom?  A half hour?  That would be my guess.  That's WAYYY too long.  

Secondly,  why are a 6 year old and an 8 year old bathing together?   There isn't enough room in the bathtub for this to happen effectively.  Neither can lie down and wash their hair without lying on top of the other.