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Clearly the sense of community on Mango Street and the importance of family to Esperanza is a key theme of this novel. In a sense, the book is all about the way in which Hispanic Americans struggle to forge themselves a productive life within American culture whilst at the same time clinging on to their cultural roots. The community is so strong on Mango Street precisely because of the shared past that all members have and the shared struggle they face in the present. Thus it is that a number of characters work hard to preserve their original culture, such as in "No Speak English," when the old woman poignantly paints her walls pink to resurrect her life back in Mexico.
What is key to realise in this novel is that, although Esperanza is always clear that she will leave Mango Street and have her own house, as is established in "A House of my Own," when she dreams about the house she will have, "With my porch and my pillow, my pretty purple petunias," she will always remain true to her past and her roots. Note how this is indicated in "The Three Sisters," when Esperanza is told:
When you leave you must remember to come back for the others. A circle, you understand? You will always be Esperanza. You will always be Mango Street. You can't erase what you know. You can't forget who you are.
The novel points towards the way in which Esperanza is indelibly marked and formed by her community and family, and how even when she leaves Mango Street, she will carry it with her. Roots are impossible to erase, and Esperanza intends to return to Mango Street once she has left, showing the all-important nature of community and family in this novel.