On an early afternoon in 2015, several days before Christmas, Caswick Naverro was driving from New Orleans to nearby Morgan City. Instead of going to celebrate with his family, though, he was headed to a funeral. His closest cousin, Josh, with whom he lived for much of his youth, who was like a brother, had been shot in the head and killed the week before.

Caswick was too far away to hear his words. He stood outside smoking a cigarette in the parking lot, wearing a white T-shirt emblazoned with his cousin’s image. He put out the cigarette and climbed in the back seat of a parked car, with two friends sitting up front.

“To God be the glory!” he intoned. “For all the things that he has done and all the things he has yet to do. This is my second funeral this Saturday of a young man. We can’t control God. He giveth and taketh away, but, I tell you today, there’s a purpose behind everything.”

The next day in Morgan City, mourners packed the church where Josh lay at rest, many of them approaching the ornate white casket to touch his shoulder one last time. Children milled at the periphery, unsure how to behave or navigate the deep well of grief and disbelief in which they’d found themselves.

“I think my cousin was here to show the people he was around that God gives great angels to people, and you shouldn’t take advantage of ’em,” he said quietly, almost croaking the words out. “He didn’t do half the stuff God had in store for him. That dude was heaven-sent. He blessed a lot of people with his presence.”

Caswick estimated that, in his 21 years, he’d been to more than a dozen funerals. The news about Josh, who was just 23, devastated him. Caswick was confused and in denial, but also filled with anger.

It’s now widely understood that soldiers returning from war zones are at risk for post-traumatic stress disorder—a mental condition that may develop in people who’ve experienced shocking or terrifying events, and whose symptoms include intense nightmares, intrusive thoughts, hypervigilance, and depression. Much less recognized or explored is how the stress and trauma of exposure to violence radiates through communities right here in the US. In one of a comparative handful of federally funded studies on the subject, researchers in Atlanta interviewed more than 8,000 urban residents, mostly young and black. Nearly a third of respondents experienced symptoms consistent with PTSD, a rate comparable to that of combat veterans who fought in Vietnam, Iraq, or Afghanistan.

Josh was among 13,463 gun homicides in the United States that year, triple the number of American troops killed in the entire war in Iraq. A large share of these deaths occur in communities like the one Caswick grew up in—poor, black and brown neighborhoods in cities such as Baltimore, St. Louis, Detroit, and Memphis, where violent crime rates have remained persistently high despite a steady drop elsewhere in the country. Nationally, gun violence remains the leading cause of death for young African American men.

“My people supposed to be happy and celebrating, but they in there cryin’,” he said, wiping his eyes and face. “They in there cryin’ and stuff, but I’m sittin’ out here and spent more time with him than any of them ever did.”

With the windows rolled up, they smoked weed while Caswick stared out at the clear day or down at the funeral programs in his lap.

“We’ve done a really poor job in New Orleans to service the needs of young people who have trauma,” said Onassis Jones, a pastor and mental-health specialist here. “We see a lot of grief, a lot of anger. If the issues are not addressed, you come across people who will self-medicate.”

Unfortunately, residents of these communities are much less likely to receive the support and care necessary to cope with PTSD. Racial disparities in access to mental healthcare in the US are stark: Studies have found that black people receive far less mental healthcare than whites, and they are more likely to live in an area with limited access to care. Far too often, young men like Caswick are left to struggle on their own.

These themes ran through all of my conversations with Caswick—the nightmares, the depression, the outbursts of anger, the self-medication. As I got to know him over the course of many months, I began to see his story as a window into a vast, undiagnosed epidemic of PTSD in communities of color plagued by violence.

Caswick entered the world of New Orleans at its most violent: The year he was born, 1994, marked the most homicides in the city’s history, at 424. He was the third of five siblings, four boys and one girl, raised by a single mother in the Magnolia Projects—known for its gang activity, rampant drugs, and frequent homicides—in the neighborhood of Central City.

“Every time I see a dead person now I go back to that moment when I was a kid,” Caswick said. “You always go back to that first body. Seen a lot of bodies since then, more than you can count. But I always think about the first one.”

The boys skirted the house cautiously before entering. Inside, they discovered a man lying curled up on a floor, with two gunshots to the head. More exhilarated than scared, Caswick and Boogie poked around the body and then retreated, waiting to see what would happen. Several hours later, they watched as an ambulance and police cars arrived, signals blaring and lights flashing, and officers entered the house.

Caswick was not yet ten years old when he saw his first body. One afternoon, he and his cousin Trayvon, or “Boogie,” were exploring some empty lots in the neighborhood when they noticed a pungent, unfamiliar smell coming from an abandoned house.

Growing up in this kind of environment can affect someone for the rest of his or her life, according to public-health experts. In the 1990s, the CDC and Kaiser Permanente partnered on a landmark study of more than 17,000 individuals, looking at the connection between adverse childhood experiences (or ACEs), including household substance use, neglect, physical abuse, or parental incarceration, and childrens’ long-term health. The more ACEs someone has—the higher their ACE score—the higher their risk of depression, drug use, and such health problems as diabetes and heart attacks, which disproportionately impact communities of color.

“One thing we know is that the first three to five years of life are super foundational for a child’s trajectory,” said Monica Stevens, an assistant professor of psychiatry at Tulane University. “The ACE scores for children and adults in New Orleans tend to be pretty high.”

Caswick didn’t know his father, who had children by different mothers in Louisiana, Jamaica, and Haiti, none of whom Caswick can remember meeting. He had a reputation as a big-time drug dealer, and the word was he was killed in the streets, though Caswick doesn’t know exactly how or when.

His mother, afflicted with lupus, struggled to feed and house her kids. Caswick and his siblings would crash at other people’s homes for weeks or even months at a time. When Caswick was eight, his mother took the family back to Morgan City, where she was from. He went to live with his paternal grandparents when he was around ten years old, and soon afterward stayed with an uncle.

That uncle, he says, wanted to “make a man” of him. “He ain’t really stop me from being in the streets or selling drugs,” Caswick recalled. “He was more like, ‘If that’s what you want to do, you know the outcome of it, so you just gonna have to deal with it when it come to you.’” Caswick did know where that path led: His two older brothers were already in and out of jail for dealing; one would end up at Angola on a life sentence for murder.

“We have moved into a frightening position where increasingly as a society we seem to be leaving individuals—particularly young men—behind, because of a lack of belief or understanding that the conditions they face are as serious as they are,” said Paul Gionfriddo, the CEO and president of Mental Health America.

Caswick remembers watching movies as a child, the ones with the “good” kids—almost always white—with nice homes, two parents, fancy watches, and pretty girlfriends. In his world, the kids with the nice cars and pretty girlfriends mostly sold drugs. Caswick’s oldest brother tried to warn him away from the streets, but then he’d come around with fist-size stacks of bills. By the time he was 11, Caswick was in the game.