The dynamic between the narrator and his uncle in James Joyce's "Araby" is an interesting one, although it's touched on briefly. In the story, the narrator anxiously waits for his uncle to return from work, as his uncle promised to give him some money to go a local bazaar. The narrator is particularly anxious about making it to the bazaar on time, as he promised to buy a gift for Mangan's sister, the girl he has a crush on. When the narrator's uncle finally comes home (much later than he promised to), it's apparent he has been drinking and does not care about his nephew's urgency. The uncle's lateness is the main reason the narrator arrives to the bazaar too late to buy anything for Mangan's sister.

Unlike the narrator, who is anxious to prove his worth and love for Managan's sister, the uncle seems to care much less for the relationships in his life. Rather than supporting his nephew, for example, the uncle stays out drinking after work and seems oblivious to the harm he causes. This flippant attitude has a direct impact on the narrator, as it ultimately sets up his despairing epiphany at the end of the short story and the realization that his childhood fantasies are absurd. 

While the narrator's dreams of love and adventure have a certain absurdity to them, the ruthless destruction of the character's dreams at the end of the story is somewhat tragic. Faced by the indifference of adults, the narrator has no choice but to amend his sensitive ways and harden his idealistic attitude. Thus, the relationship between the uncle and the narrator illustrates the way uncaring adults (who presumably have already been hardened by disappointment) shatter the idyllic worldview of children and force children to become hardened and cynical. Viewed from this point of view, it's clear the relationship between the narrator and his uncle is one of the most important aspects of "Araby."