Additionally, the party has possibly stolen Rosaura's faith in human nature and her trust that there is such a thing as impartiality in life.
In the story, Rosaura is excited when she is invited to Luciana's birthday party. Luciana is Senora Ines's daughter, and Rosaura's mother works for Senora Ines as a maid in her household. Although Rosaura sees nothing wrong with being invited to Luciana's party, Rosaura's mother fears that, by attending, Rosaura is setting herself up for future disappointment. She warns Rosaura that Luciana isn't really her friend, but Rosaura refuses to listen.
At the party, Rosaura's mother's words prove prescient. Rosaura is accosted by a girl wearing a bow in her hair. The girl demands to know who Rosaura is and what right she has to be present at the party. Indignant at the girl's patronizing rudeness, Rosaura replies that she is Luciana's friend. The girl scoffs at this proclamation; she insists that, as Luciana's cousin, she has full knowledge of who Luciana's friends are. Since she's never heard of Luciana and doesn't know of her, she argues that Rosaura can't possibly be Luciana's friend.
Rosaura is able to ignore the girl's rudeness and to enjoy the party. Since Senora Ines treats her with such courtesy and kindness, Rosaura feels confident that the girl's behavior is just an aberration of sorts. During the party, Rosaura is the only girl Senora Ines trusts to be in the kitchen. Rosaura is also the only child called upon to help serve the hot-dogs and cake to the other children. Meanwhile, the other children enthusiastically and unequivocally welcome Rosaura's participation in the party games.
Rosaura is so happy that she fails to realize the real reasons she has been asked to help with the food. As the daughter of the maid, Rosaura is considered the natural and interim extension of her mother at the party. Notwithstanding Senora Ines's kindness to Rosaura, the older woman still considers Rosaura the daughter of the maid.
At the end of the party, Rosaura becomes greatly disillusioned when Senora Ines hands her some money as a reward for helping her during the event. With this act, Senora Ines dispels any illusion Rosaura has of being Luciana's equal. Rosaura comes to realize the truth of her mother's earlier words: Luciana can never truly be her friend. Essentially, the party has stolen Rosaura's innocence; she now knows that the presence of seeming impartiality is only superficial at best.