I think the evidence that best supports the conclusion that the narrator is telling this story with a particular child in mind is the repetitive use of the second person, addressing directly to the reader.
The two elements of Shackleton's South! that are common traits of a memoir are the vivid description of the landscape and The first-person point of view or style of narration.
Brinker Hadley is tall and athletic looking. He likes to feel that he is in charge and over everyone else, so he is involved in lots of clubs and activities.
