Like in the source material "Alice's Adventures in Wonderland", the sister is never given a name. Although the introduction never refers to whether she's older or younger, in the end it refers to Alice as "this same little sister of hers" indicating she is the older of the two.
In the original book by Lewis Carroll, she isn't seen as a strict, no-nonsense sibling or giving Alice a history lesson. But she still enjoys books, however, Alice loses interest in what she is reading as it is a book with no pictures or conversations in it. After Alice wakes up from her dream, she listens with interest to all she dreamed about. Alice then goes home for tea while her sister stays on the riverbank, thinking of everything Alice had told her and imagining it for herself.
Alice Pleasance Liddell (the inspiration for the Alice in the story) had an elder sister named Lorina Charlotte Liddell and a younger sister named Edith Mary Liddell.
Instead of a third sister, "Alice's Adventures in Wonderland" instead referred to a brother who is never mentioned in the film:
- (Alice thought this must be the right way of speaking to a mouse: she had never done such a thing before, but she remembered having seen in her brother’s Latin Grammar, “A mouse—of a mouse—to a mouse—a mouse—O mouse!”)
Role in the film
In the film, she is first introduced to reading Alice's history lesson in the park near the river bank. Halfway through, she notices Alice's lack of attention. Alice tells her that there is simply no need for a book without pictures, but her sister returns that there are great deals of books without any pictures. She did appear to express a mild amusement at Alice's musings of her own world that had books with only pictures. Alice then sneaks away from her and follows the White Rabbit, thus beginning her adventure. She is not seen until the end of the film when she wakes Alice from her dream of Wonderland. At first, she is disappointed at Alice for dozing off and dreaming up such nonsense, but she is able to accept her little sister's wild imagination. They, along with Dinah, then head home for tea.
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