Oscar Cásares did not expect immigration to become quite the issue it is now when he started putting together his latest novel, “Where We Come From.” He expected it to be A Thing — this is the United States, after all — but he wasn’t expecting it to be The Thing.

“It sure turned out to be,” Cásares says. The writer and University of Texas professor is at the U.S.-Mexico border quite literally as we speak, about three-quarters of a mile from the Rio Grande, working on a story for Texas Monthly.

“Where We Come From,” out this month from Knopf, didn’t start out as a book with the zeitgeist in mind.

“I wanted to write a novel about what happens after people immigrate, after people leave the border and come back,” Cásares, a Brownsville native, says. “I had grown up on the border and watched my brothers and sisters move away and come for the summer. I knew a lot of people who had roots there via their parents but knew very little about it.”

After his mother dies unexpectedly in “Where We Come From,” Orly, all of 12, is sent from a comparatively wealthy home in Houston to live in Brownsville for the summer with his great-aunt and godmother, Nina. Orly’s dad is an advertising executive. Nina is a retired school teacher who is taking care of her ailing, cranky mother.

We soon learn that coyotes — the colloquial term for smugglers who run people across the border illegally — are using the small casita in Nina’s backyard as a “stash house” to bring undocumented immigrants north. What started as a favor for Nina’s cleaning lady has metastasized into something Nina no longer controls.

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When a child named Daniel arrives in Nina’s yard having narrowly dodged ICE agents, he and Orly soon form a bond.

Cásares weaves in sketches of folks the main characters run into along the way — a teacher of Orly’s, a coyote, a Brownsville cop, a waiter — as a way of touching on the variety of immigrant experiences.

“I knew I wanted a story involving a child from a much more privileged world who had roots in this border culture,” Cásares says. “I knew I wanted him to come back and learn something about that family that he came from."

Growing up around the border, Cásares says the distinction between documented and undocumented was minimal. "Being undocumented didn't have near the stigma that it has currently,” he says.

That said, that experience of being undocumented became a larger part of “Where We Come From.” From the start, Cásares wanted the sketches of the various secondary and tertiary characters in the novel.

“The cliched term is that undocumented people are living in the shadows,” Cásares says. “Not only are they trying to escape being spotted and the consequences thereof, but they have also been marginalized and we don’t understand the impact that they have on our lives. Part of that is human nature. We are all occupied by our own struggles, but part of it is systemic.”

“Where We Come From” has been reviewed as a "quiet" novel, and that makes Cásares bristle a bit.

“I think that there is an expectation that when you hear 'this is a story about the border,' you are going to get a particular type of novel,” Cásares says. “It’s going to be suspenseful and there’s going to be going to be a lot of human misery. I didn’t shy away from that, but that isn’t all there is. I wanted this novel to be bigger than the sensationalized stories that you read and hear and see.”

That’s another reason why the brief looks at supporting characters are there. “I wanted to get at least a little bit into what is going on in these people’s personal lives that drives them to take these enormous risks,” Cásares says. “Our government wants us to believe people are coming here to take advantage of an American way of life. In fact, if they could make it in their home countries, they absolutely would.”

In June of last year, as Cásares was editing “Where We Come From,” he wrote an op-ed for the Washington Post about family separation and detention. It is titled “A child doesn’t cry in Spanish or English. A child simply cries, and we respond.”

“I didn’t want to get into a shouting match about immigration,” he says, “but that piece really is the non-fiction angle on this same narrative. This sort of immigration is about the urgency to get out of harm’s way, and it really isn’t much more complicated than that.”

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