This short tale, narrated by a North American farm girl, does not have any outrageously hideous or sensational deeds. Nonetheless, Munro manages to discuss the American concept of individuality in children, whose will will not always prevail while they are minors, even if they expend the intense effort to control their own destiny, as this narrator does. In this case, such expressions of individuality ultimately lead to moral maturity foreshadowing the narrator's adulthood. In essence, the story is about the narrator's struggle to become an adult.
The narrator's efforts to be unique are underscored by the fact that this fox farming family is so average, living in a community (Jubilee) where the family is the central focus of all the characters' lives--and yet despite the lack of outside countercultural advocacy that surfaces in urban areas, the central character rebels on her own. The narrator describes her home as having a "warm, safe, brightly lit downstairs world" but then turns around and describes her bedroom (upstairs) as "not finished" and as containing knick-knacks that are "very sad to look at". This contrast between the positive and negative aspects of the setting foreshadows the narrator's general satisfaction with her life but not everything about it, which she ultimately fails to change to suit herself. While she concedes that "we had rules to keep us safe" and that "I worked willingly under his[her father's] eyes, and with a feeling of pride", indicating her loyalty to her family, she carries a noticeably contrasting mindset in the bedtime fantasy world in which she "went on with one of the stories I was telling myself from night…took place in a world that was recognizably mine, yet one that presented opportunities…as mine never did". The latter statement foreshadows the climax of the story, when she decides she is willing to cross the line of ignoring the welfare of her father in order to fulfill her long-sought goal of real influence and mild rebellion (when she knowingly lets the horse out of the yard). Additionally, this climax is preceded by the narrator's use of her younger brother, Laird, to create a mild stir in the family when she places him up on the top beam, from which her father must remove him. Again, she seeks to have power within her family structure which she knows will not be granted willingly at her age, so she seizes it anyway. However, as she is still a child she seizes this power through illegitimate means (disrupting family harmony and making her parents worry about her brother's safety) rather than through legitimate means (for example, heading a family or an organization, the former being impossible at her age and the latter being almost impossible).
Coupled with her attempts to gain power within the family is her desire to form her own opinions on the validity of entrenched customs and institutions. As a child, she has never questioned the need to kill animals when they are ill and/or have outlasted their usefulness. She has taken it for granted as a part of farm life, which is as her father wants it (otherwise, he would permit her to observe the shooting procedure); however, in her desire to grow up she wants to see it firsthand. While some would write this off as ordinary childhood curiosity, it could also be her conscious desire to form her own opinion of what goes on. After seeing her father shoot the horse, she "felt a little ashamed, and there was a new wariness, a sense of holding-off, in my attitude toward my father and his work." She may have watched the shooting in order to manufacture the opportunity to question her family's institutions. And question them she does, in an effort to attain the adult characteristic of personal autonomy. This can be seen again when the narrator becomes petulant--when her mother and grandmother apparently attempt to train her in how to be a "girl", presumably so that she will grow up knowing how to be a "lady". Her grandmother attempts to give her instruction in traditional feminine body movements and positioning, which coincides with her awareness that her brother, as a male, is developing his strength at a faster rate than she is. She rebels against this by trying harder than ever to appear as a tomboy. Interestingly, she doesn't mind outdoor labor with her father ("I worked willilngly under his eyes", she says); this is significant because it suggests that she is not rebelling against her parents specifically--she is merely standing up for her personal autonomy, as well as the autonomy of the horse to be physically free of the property. She (newly, of course) views the horse as sharing her plight, but in the end she is reconciled with the facts ("we needed the meat to feed the foxes, we needed the foxes to make our living" and "Maybe it was true" that "She's only a girl").
Just as this story is about a young girl trying to seize influence in the family system and express her autonomy by letting the horse escape, so it is also about her efforts at self-control. The evidence that she also wants to control herself is shown by the guilt (as displayed by her honest crying at the table after everyone found out that she had left the gate open on purpose and, also, by the guilt she feels when she sees the coat Laird wore when she stuck him up on the top beam in the barn); her quest for a combination of independence and influence coupled with self-control is her means to get where she wants to be, which is simply to no longer be, as her father pronounces in her defense, "…only a girl."
This reconciliation and corresponding guilt that she feels for causing her father to have to expend time and energy tracking down the horse which she knowingly allowed to get away exemplifies the developing of her conscience--her superego, which is part of being a mature adult; it is a step in her struggle to NOT remain a "girl".
Growing up is a two-pronged development; in order for a child to grow up, he or she must develop an individual personality (shown by the narrator's attempts to influence the happenings in her family and form her own opinions even if she has to be disobedient to get the necessary exposure) and its accompanying moral development (the narrator's sense of guilt for inconveniencing her father will lead to her understanding of how she can be her own person while also respecting the norms of society).