It wasn’t the first time he had attempted suicide in or around school grounds, administrators said. He’d been depressed, and behaving erratically, with signs that he was using drugs and “huffing” gasoline. There had also been signs of sexual abuse, involving not only him but also a younger brother and male cousins he lived with. Every time one of the boys showed new signs of abuse or talked about suicide, school officials said, they called the tribe’s child protection unit, and every time they were told the same thing: “It’s still under investigation.”

The child was not removed from the home. Then in December, two weeks after his 14th birthday, the boy hanged himself at home and became the first in the recent string of nine suicides.

His case was lost, it seems, in the web of tribal bureaucracies and federal oversight bodies that are long on backlogged cases and short on funding. The tribal child protection unit, for instance, currently has two investigators for the entire reservation, which the federal census puts at more than 18,000 total residents (though tribal officials say is closer to 40,000). The two investigators are responsible for handling upward of 40 new cases a month, and hundreds more in the long-term case management system.

About a month after the boy died, a 14-year old cheerleader killed herself. Soon after, rumors of an all-too-familiar detail started to spread: Before her death, the girl told friends that her stepfather, a longtime teacher and coach at her school, was sexually abusing her. What followed broke the usual mold, though: Her friends came forward to tell school officials. Charles Roessel, a member of the Navajo Nation and director of the federal Bureau of Indian Education, which oversees the school, said administrators acted quickly to suspend the accused teacher and refer the case to federal investigators. No charges have been brought.

Shortly after his suspension from the federal school, the cheerleader’s stepfather was brought on, according to school officials, as an unpaid intern by the reservation’s Shannon County school system, which is overseen by the state. His job was to shadow one of the system’s principals so that he could learn to be a school administrator. The stepfather did not respond to requests for comment.

TRIBAL LEADERS and experts are struggling to understand the recent suicide epidemic (specifics on many of the cases aren’t widely known), but there’s general agreement on one underlying cause: the legacy of federally funded boarding schools that forcibly removed generations of Native American children from their homes. Former students and scholars of the institutions say that the isolation and lack of oversight at the mostly church-run schools allowed physical and sexual abuse to run rampant.

“My grandmother used to tell me that she didn’t think she was pretty,” said an E.M.T. friend of mine who responds to a suicide attempt every week or so, “because when the priests used to sneak into her dorm and take a little girl for the night, they never picked her.”