Answer and Explanation:
The author decides to open the novel presenting the characters and motivations of the protagonist Sierra in making a surprise for her grandfather. With this, the author of the book shows how the family institution is important for the development of the story and how it will have a strong weight in the course of the plot.
He decides to present the characters according to the relationship between them and the protagonist, the same can be seen in the presentation of the settings that are presented according to the relationship between them and the protagonist becomes relevant. This shows how the whole narrative revolves around Sierra and the responsibilities she has.