On Sunday, thirteen-year-old Cayman Naib was found dead of a self-inflicted gunshot wound after a four-day search. He used his father’s gun, police say, and an ill-fitting trigger lock did not prevent it from firing.

Epidemiologist Douglas Wiebe, who studies risks associated with gun ownership at the University of Pennsylvania found in a study of adults that “the risk of suicide is three times higher for people who have a gun in the home than for people without guns. Guns in the home also raise the risk of homicide and accidental deaths.”

The vast majority of people who attempt suicide with guns—85 to 92 percent—end up dying, according to David Brent, an adolescent psychiatrist and suicide expert at the University of Pittsburgh. Guns are 2.6 times more lethal than suffocation, and 270 times more so than poison.

“One of Brent’s studies found that adolescents who killed themselves were twice as likely to have lived in homes with guns than youths who attempted suicide but survived. He also found that the availability of a gun in the home was a bigger risk factor for suicide in youths than psychiatric disorders,” writes The Philadelphia Inquirer‘s Stacey Burling.

Child psychiatrist Anthony Rostain, who works at Penn and Children’s Hospital of Philadelphia, said that teenagers can be easily overwhelmed by negative feelings. He and others added that young people may also have less control over impulsive thoughts.

“One argument against focusing on guns is that people who want to kill themselves will find other means. Suicide experts say that has not proven true. Rostain said he had talked with many young patients at Children’s who survived a suicide attempt and were glad they did.”

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