Samantha Kuberski hanged herself with a belt from a crib. She was 6.

Razy Sellars was 11 when he took his life. Gabriel Taye was 8. Jamel Myles was 9.

Suicide in elementary school-aged children remains rare: 53 children aged 11 and younger took their lives in 2016, the last year for which the Centers for Disease Control and Prevention has data. But medical professionals and researchers have noted alarming increases in the last decade – deaths more than doubled from 2008 to 2016 – and rising numbers of young children visiting emergency rooms for suicidal thoughts and attempts.

"You hear of all these kids taking their lives, and you just don’t understand why it is," says Christine Sellars, Razy's grandmother. "I don’t know if it’s the changing times, the way kids are brought up today or the peer pressure.

"It's just so sad."

The reasons for the increases are unclear. Few researchers have examined suicide before age 10, so little is known about suicidal thinking and behavior in young children.

But as they look more closely, themes are beginning to emerge. Attention deficit hyperactivity disorder, which can make impulsive youth still more impulsive, was a common characteristic found in a 2016 study by researchers from Nationwide Children's Hospital in Columbus. So were arguments or disagreements with family members and friends.

Unlike in suicides of adults, depression didn't appear to be a major factor.

Many of the deaths followed episodes of bullying. Social media can amplify those attacks – and make them impossible to escape.

Among cases that involved bullying:

• Schoolmates called Sellars gay and made fun of his clothes before he took his life in Akron, Ohio, in May, his mother told reporters at the time. After his death, his older brothers were taunted on Snapchat and Twitter. His mother said some suggested they should kill themselves, too.

• Stormiyah Denson-Jackson, 12, was bullied at her Washington, D.C., boarding school, her mother told a local television station. When the girl reported it to school officials, her mother said, she was herself accused of bullying. She was found dead in her dorm room in January.

• Taye was assaulted by a fellow student in a school bathroom two days before he hanged himself in Cincinnati in 2017, his family said.

While it's not clear that bullying causes suicide-related behavior, the CDC says it's among the risk factors that increase the likelihood that a young person will consider and/or attempt to take his or her life.

Children who have disabilities or differences in learning, sexual/gender identity or culture are often most vulnerable to being bullied, according to the CDC. (The federal agency says acknowledging risk factors is not the same as blaming victims.)

Psychologist John Ackerman is the suicide prevention coordinator at the Center for Suicide Prevention and Research at Nationwide Children's Hospital. The child psychologist tries to strike a balance of reassurance and alarm.

Only about 10 percent of people of any age who attempt suicide ever end their lives, he notes. But at the same time, he says, "We don't want to normalize suicidal behavior."

One question researchers are probing: Do children as young as 6 understand the finality of death? Can those who have died by suicide be said to have been aware of what they were doing?

"I originally had my doubts," says Arielle Sheftall, lead author of the 2016 study. "I realized they do know what I’m talking about, and about the concept of death and life."

That's borne out in the data, and in reports from concerned parents. The website of the Berkeley Parents Network includes several posts from parents of children ages 5 to 7 who have said they wanted to kill themselves, in some cases with detailed plans.

Ackerman says most youth who attempt suicide have had suicidal ideation or thoughts of killing themselves.

These can escalate to attempts – in some cases within hours, Ackerman says. In other cases, it can take years.

Even when ideation doesn't lead to attempts, it can indicate problems ahead. Researchers have found that children who considered suicide before adolescence had higher rates of mental health and addiction disorders as adults than those whose first thoughts of suicide came later.

"We want to get the message out and do need to prepare families," Ackerman says. "We need to ask very targeted questions of young people to get them the support they need."

Monday is World Suicide Prevention Day. The International Association for Suicide Prevention works with the World Health Organization, the World Federation for Mental Health and local groups around the world to raise awareness and money to fight suicide.

Is hate the reason?

"Hate" is what killed Jamel Myles, his mother says. Myles' father is of mixed race; his mother is white. The Denver boy recently told his mother he was gay.

"Hate because people can't teach or learn to love each other regardless if they're gay or black or believe in something different," Leia Pierce says. "Hate took my son because this world lacks acceptance."

Myles' father, Kenneth, who is no longer with Pierce, says he doesn't believe his son was trying to kill himself.

Kenneth Myles believes the boy died while playing the "choking game," in which participants strangle themselves to induce euphoria through brief hypoxia, a lack of oxygen to the brain.

He cited nail marks he saw on his son's neck and information about the game on a laptop to which the boy had access.

The medical examiner in Denver has ruled the boy's death a suicide.

Carl Walker-Hoover was 11 when he wrapped an extension cord around his neck and hanged himself from a rafter in his family's Springfield, Massachusetts, home in 2009.

His death drew national attention. Brenda Hogan remembers it well. She was teaching Walker-Hoover's younger sister in preschool at the time.

"It wasn’t heard of back then," she says. "Now you hear all the time about kids trying to kill themselves."

She's thinking in particular of two girls she knows, ages 9 and 12, who have survived abuse. Both have threatened suicide.

Carmen Garner, a cousin of Hogan in Washington, D.C., has a tattoo of a Band-Aid on his left wrist. It's a reminder of his own suicide attempt in middle school.

Now Garner, 40, teaches art to elementary school students. Often, he says, it's more like therapy.

One third grader tried to jump out a window, he says. Another threatened suicide after his father was badly injured in a crash. A third said he wanted to die after seeing family members killed in his home.

Garner blames a toxic mix of violent video games, overuse of social media and dangerous neighborhoods. "Everything’s desensitized," he says. "Death is something these kids know about. They have the resources to get all the negativity” – but not to get help.

"We need to take care of our children," he says. "Children need time to heal when they have traumatic experiences."

A link between trauma and suicide seem both logical and likely, Ackerman says, but there is still much researchers don't know.

Poverty is probably not driving the increase, he says, but it can be a risk factor for a "younger person feeling worthless and that the future holds very little in store for them."

"That can happen very early," he says.

Suicide has run in Razy Sellars' family. His father, Andrew, hanged himself shortly before Christmas 2011. His mother's father, Charles Fay, shot himself to death in 1992.

But never had a victim been so young as Razy.

Christine Sellars, Razy's paternal grandmother, says Andrew's death hit the boy particularly hard – first, when it happened, and again two years later, when he learned it was suicide.

"Razy just was attached to my son so much," she says.

Still, she says,"he never seemed to have a problem until things started going haywire at school."

The boy kept getting into fights. His grandmother says he was bullied. He was moved to a school for children with disciplinary problems, but often refused to go.

On May 24, Razy hanged himself in his home with a belt, just as his dad did.

His brother Riley, 15, found him; their maternal grandmother, Dolores Fay, helped him take Razy down from the bar in the closet.

"He was cremated and buried on top of his dad," Fay says.

Fay wishes she had discouraged Razy and his brothers from playing the violent video game Fortnite. She wonders what's wrong with society that children want to end their own lives.

"We all own a piece of this," Fay says. "It takes a village...and then somehow we failed."

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