If you watch the part when Anastasia is in the palace and is standing in front of the picture, you can see that the little Anastasia is on the right side of her mother. Then later on when Anastasia is looking at the picture little Anastasia is on the right side.
Ummm - I may be mistaken but I think you are the one who is incorrect. If what you say is true (I've never seen the movie), then there is no slip-up. If little Anastasia is on the right side both times, there is no mistake.
no, s/he said "right side of her mother" which would be the left side of the picture, because the mother is facing the camera. then s/he said "right side of the picture" which would be the mother's left side, so it really is a mistake. If you're going to comment, make sure you read the post completely.
Actually, if you really watch the movie, I've seen it many times, they are two different paintings. After standing in front of the first one, they walk up some stairs, which is the other one at which she looks. So this is not a slip up!