The disturbing goodbye was captured in a series of ISIS propaganda photos last month.
Supporters of the terror group claim the boy was used to help take the village of Ghazl near Aleppo, Syria.
But Omri is not alone. The use of child soldiers far predates ISIS, but what concerns researchers and policymakers is that ISIS' use of boys and girls does not follow the trends of previous conflicts.
ISIS does not use those under 18 because they provide specific technical advantage in combat or because they are short of fighters. Child soldiers are seemingly treated no differently than adult soldiers, according to a new study published Friday in the CTC Sentinel.
What this means in the self-proclaimed Islamic Caliphate is there simply is no sanctity accorded to childhood.
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Researchers say that sad fact could not only have implications on the battlefield, as the chance for military encounters between coalition-backed forces and ISIS child fighters increases.
The findings also show that eliminating ISIS will be much more complicated than killing its leader, Abu Bakr al-Baghdadi, or disarming his fighters. There's the question of what to do about potentially thousands of indoctrinated children left behind.
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The cases of Omri and the 88 other children eulogized by ISIS in the past 13 months are documented in the study, which includes an open source database of ISIS child propaganda, the first of its kind.
"What this database points to is the fact that use of children is far more normalized," Charlie Winter, the report's co-author, told CNN. "They are not just being used to shock people in execution videos. They are being used for their operational value as well. This is something that sadly we have to expect to increase and accelerate as the situation becomes more precarious for ISIS in the years to come."
Researchers from Georgia State University have been combing Twitter and ISIS channels on Telegram to record the children's ages, dates, nationalities -- anyone 18 or younger. The trends are striking and deeply troubling.
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Disturbing statistics
Most of the children are from Syria. Most were killed in Iraq. Of the 89 cases, 39% died detonating a vehicle born IED device and 33% were killed as foot soldiers. Some 4% killed themselves while committing mass casualty attacks against civilians, and 6% died as propagandists embedded with brigades.
Researchers say they've noticed an emerging ISIS tactic.
Nearly 20% of the children killed were inghimasis, or "marauders" who carried out so-called "plunging attacks." That's a military operation in which a group of fighters attack an enemy position before blowing themselves up.
Last month, five adult ISIS fighters flanked by three children infiltrated the Tariq base in Iraq. ISIS boasted that the group attacked from within for three hours, killing people before detonating their suicide belts. Winter says this shows the children are not being used to replace adults. They are integrated into ISIS' military operations -- often with parental consent.
"It's interesting the degree to which the parents are giving the organization access to their children," said Mia Bloom, the co-author of the report. "It's not a coercive endeavor like what we saw in Africa. The kids are not being kidnapped. The kids are not being coerced. For the most part, what we're seeing is kids posing with a big smile and at least in one case saying goodbye to the parents."
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The next generation of jihadists
ISIS has long made clear its intent to raise the next generation of jihadists, calling them the "cubs of the caliphate." In a recent publication of their English language magazine Dabiq, it encourages mothers to sacrifice their sons for the self-proclaimed Islamic state.
"As for you, O mother of lion cubs. ... And what will make you know what the mother of lion cubs is? She is the teacher of generations and the producer of men," the article reads.
Winters says what is happening is very similar to how Saddam Hussein used child fighters in Iraq.
"Even right down to the cubs of the caliphate, there was the cubs of Saddam," he said.
"ISIS is integrating children into its project in a way that is more reminiscent of a state than a non-state actor. It's thinking with the long term in mind. It's not just bringing children into its ranks and using them immediately on the battlefield. What it's doing is bringing them in, indoctrinating them, training them, spending a lot of time instilling them with jihadist ideology."
Bloom says the database of 89 children killed is a snapshot of a larger phenomenon. She estimates there are at least 1,500 ISIS child fighters, which poses unique challenges for the coalition on the battlefield and in terms of rehabilitation.
"The way you got the kids out of child soldiering in Liberia, Uganda or Mozambique was you use two things. You use the family and you use religion," Bloom says.
"The problem with ISIS is that they've distorted the religion, and the families are colluding with ISIS to allow them access to the kids. So there's additional challenges, and we don't have a really good template to use ... it's a big problem."
