And also on the 'expressions' it should be noted there is a good possibility some of these were intentional, such as AA's lip biting pose. It seems she did try to look like AN.
This is not impossible or unusual. Actors do this all the time, try to use their expressions and gestures to make up for a lack of actually looking like the person they are portraying. Another 'rock star' example- at a concert, I met an impersonator of the singer I had come to see. The way he moved, his facial expressions, his gestures, his poses, were SO much like the singer it gave me the chills. I went off with a glowing opinion of him. He appeared to be the singer's long lost twin. But when I posted his pictures on the singer's website, people posted that they didn't see a resemblance, other than the way he was dressed. So much of it was that he had this guys' mannerisms down pat, but he really didn't look like him in pics (though at times he, too, tries to mock certain expressions)