Also, about the contact between the sisters, there is a deleted scene on youtube showing the sisters joking in a dressing room before the coronation, picking out dresses together, so the writers thought about showing some contact between the sisters. Seems that they wanted to show that the sisters grew up in 2 very different environments; Elsa in a self-imposed isolation and Anna in a imposed isolation. The king said they would "reduce the staff" and LIMIT Elsa's contact with others, including Anna. Limit, not eliminate. So we can assume there was some contact, but the actual amount is not important to the story, olny that is was limited. This limited conact with others, I believe, is what the writers use to lead to Anna's romantisizing the world and identifying with the paintings on the walls (remember in the song she starts taking to them and then later putting herself into the romantic pantings as the center of attention.) She is starved for attention and so when someone (Hans) shows her attention, she overreacts and thinks it must be true love...