When my friend asked me about what "A House On Mango Street" is about I didn't know how to answer him. So I told him it was like a modern "A Tree Grows in Brooklyn" except told in vignettes. Which is fairly accurate because they are both about poverty through the eyes of a child but more than that.
What I love about both books is that they have a searing kind of truth to them but at the same time it wasn't depressing. Books are often either swallowed in there own depression or avoid topics to keep the story from it. I think that writing can be about anything and not be depressing if it is written well and creatively written, with good symbols (metaphors and similes) and description. For example the chapter "What Sally Said" is about a beautiful girl named Sally who is hurt by her father. When talking about Sally's father hitting her she says "But Sally doesn't tell about that time he hit her with his hands like a dog, she said, like if I was an animal." It would be so easy to give a graphic description of Sally being hit but instead the cruelty is implied. I think this is much more powerful than graphically describing Sally being hit because more is left to the imagination. We see Sally being hit and are upset by it but no description of blood is necessary to move us.
At the same time the book doesn't avoid painful topics that would be part of the main character, Esperanza's, life, such as poverty and death, to keep the book from being too sad. There is a sort of truth that only a child can see. Such as how Sally's father loves Sally or like how in "A Tree Grows in Brooklyn" Betty Smith can write about Francie's father being a alcoholic but Francie loves her father because she knows that he is a wonderful person despite his addiction.