Remember that this incredible series of vignettes explores life in a barrio from the perspective of a young girl growing up as an immigrant among immigrants in a different country. The challenges that these immigrants face are very similar in terms of the difficulties they have to overcome in order to survive in this world of theirs. Firstly, Louie's "girl cousin" has to cope with living without her own family, who are in Puerto Rico. Whilst selling Avon products gives her free make up, she still remains horrendously trapped by having to baby sit Louie's sisters:
She can't come out--gotta baby sit Louie's sisters--but she stands in the doorway a lot, all the time singing, clicking her fingers, the same song...
This points towards a larger theme in the novel which is the position of women in this kind of world and the opportunities or lack of opportunities that they have.
Secondly, Louie's other cousin shows how many immigrants turn to crime in order to try and get ahead in this bewildering new world. We have an excellent example of how the rather naive narrator is not aware that this "great big yellow Cadillac" is not stolen, and how she and others have a ride in it and play with the electric windows until they hear sirens. This child-like innocence is maintained as the narrator and her friends wave at Louie's cousin as the police take him away.
Therefore, this vignette, like the entire novel, expose the harsh realities of life of Latino immigrants in the States through the eyes of a youthful and naive narrator, whose acceptance of these "realities" make them all the more shocking.