For a thirteen-year-old girl, Esperanza seems to think a lot in metaphors. One of her favorites? A river. To her, this river represents the social divide that separates her from Miguel:
"But now that she was a young woman, she understood that Miguel was the housekeeper's son and she was the ranch owner's daughter and between them ran a deep river. Esperanza stood on one side and Miguel stood on the other and the river could never be crossed." (2.52)
These lovers aren't star-crossed—they're river-crossed. You may have heard of this conundrum before: you know, Miguel and Esperanza are from two different social classes; Miguel is from the wrong side of the tracks; he's a Montague, and she's a Capulet; she's a human girl, and he's a sparkly, sparkly vampire. Get it? But remember, this little obstacle never manages to keep the lovebirds apart for long.
So does Miguel cross over to the wealthy, privileged side of the river? Nope, it doesn't quite work like that. Instead, Esperanza's father is murdered, her house burns down, and her family loses everything. She moves to the United States with her former servants and becomes a peasant, just like them. This is riches to rags.
Here's the deal: in the United States, there's not even supposed to be a river. The U.S. is supposed to be the land of opportunity, where anyone can make it big, no matter their race, religion or former social standing. Unfortunately, life in the U.S. isn't quite as easy as Esperanza and Miguel expect it to be. No matter how hard they work, they're held back by prejudice and pitiful working conditions. In a desperate moment, Esperanza looks at Miguel and tells him he's "still a second-class citizen" (13.49). He's still standing on the wrong side of the river.
But when Esperanza starts to feel more hopeful, she finally has a vision of herself and Miguel as children, eating mangos on the same side of the river (14.103). It's then that she finally takes Miguel's hand—and we see some pretty nice things in their future.