How does Cisneros play around with connotation and denotation with the word "only"?

(example: "I am the only daughter and only a daughter") ?

Cisneros plays around with connotation and denotation with the word only by using the word in different ways. As in this example sentence, it says they are the only daughter, inferring that there is one female child, but they say they are only a daughter, inferring that they feel they can be nothing more than a daughter.