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A 10-year-old boy who died after hanging himself from a tree is apparently the second Idaho youth killed while playing a choking game.

The Fremont County sheriff's office (search) said Dalton Eby apparently was playing a game known as the "pass-out game," trying to cut off the oxygen supply to his brain to achieve a type of "high."

The boy's mother reported him missing last Thursday night when he failed to return home after visiting a friend. Search and rescue crews found his body Friday, hanging from a tree near his Island Park home, the sheriff's office said in a statement.

"Dalton was found with the rope looped around his neck," the sheriff's office said. "There was no sign of a struggle, nor was there any physical evidence to indicate anyone else had been at the scene."

The statement added, "During the course of the investigation it was learned that there is a game that is common knowledge to many of our youth. A game known as the 'pass-out game,' the 'fainting game,' the 'tingling game,' or the 'something dreaming game' — to name a few," the release said.

Dalton's parents had never heard of the game, and neither had the parents of his friends, the sheriff's office said. That was also the case three months ago in Nampa, where 13-year-old Chelsea Dunn (search) was found dead after apparently hanging herself in her closet.

A police investigation into her death was inconclusive, but Dunn's family believes she died accidentally while playing the game, which was popular with a group of girls at her East Valley Middle School.

Six girls at the Nampa school were suspended for a day after school officials reviewed a security camera videotape that showed the seventh graders choking each other in a hallway.

Dalton's father, Dave Eby, did not want to comment on Fremont County investigators' theory that his son also died while participating in a voluntary asphyxiation game. After burying his son Monday, he told the Post Register newspaper he wanted to thank his neighbors for their "generosity and caring during this hard time."

Young teens and children lack the judgment to understand that making themselves pass out can be fatal, said Connecticut-based child psychologist Dr. Lawrence Shapiro (search), the author of "The Secret Language of Children: How to Understand What Your Kids are Really Saying."

Though the so-called game is new to many adults — including himself — Shapiro said it's likely something that children have been doing for a long time.

"That's scary. I can't say that I have heard of this before, but it's not that surprising because kids do all sorts of crazy things," Shapiro said.

In addition to talking to kids about drugs and alcohol, parents should also discuss risky behavior like the pass-out game, Shapiro said.

"Younger kids don't know that they can die from this, that it's a very dangerous activity. Sometimes kids hear about it, that other kids are doing it, but they don't hear the rest of the story, the risks," Shapiro said. "It's like diving into a pool in the shallow end — parents have to tell their kids not to do it."

Nathan Hoiosen, a school resource officer with the Nampa Police Department, said youngsters think the choking game offers a "safe" buzz compared to drinking or doing drugs.

"It's one of those undetectable things, no signs until it's too late," Hoiosen said.

Children have been playing hyperventilation or asphyxiation games for decades, he said, but using ropes or other ligatures seems to be a new trend.

"It's scary, though," he said. "You wish you could just take the kids and shake them and say, 'What are you thinking?'"