A photograph of Aylan Kurdi, a 3-year-old Syrian child, lying face down and lifeless in the sand on a Turkish beach, has sparked anger and anguish worldwide. It's raised a difficult question: Why did Aylan's family leave Syria and decide to take the journey that led to his death?

The answer to that question is equally uncomfortable: By staying in Syria, Kurdi would have risked becoming one of the hundreds of other 3-year-olds killed by the civil war there. These children's deaths are little acknowledged by the international community, but a variety of activist groups have recorded their deaths in the hope that they won't be totally in vain.

One group which tracks the deaths in the war, the Syrian Revolution Martyr Database, has detailed records for the deaths of at least 232 children aged 3. The real number may be far higher: The organization, which is run by opponents to the Syrian regime, notes that in many cases the age of the child is not known and thus cannot be recorded. In other cases, the death itself is never even recorded.

A closer look at the database's details reveals more horror. Of the 232 known deaths, almost half were killed by artillery fire. Most of the rest were killed either by aerial bombing or gunfire, with a smaller amount reported to have died from a variety of other causes – including, in one case, a slit throat.

Children of other ages suffered as well. In total, the Syrian Revolution Martyr Database found evidence of almost 2,000 children under the age of 10 who had been killed since the fighting began. Estimates from other groups  may skew far higher – the Syrian Observatory for Human Rights, a group based in Britain, has said that at least 11,493 children have died since the war began. These estimates do not include children like Kurdi who died after fleeing the chaos.

Attempts to count the dead in Syria have become one of the most divisive parts of the response to the conflict. The Syrian Observatory, perhaps the most widely cited of all the groups attempting to keep tally of the deaths, says it has counted the deaths of over 220,000 people since the war began. The Syrian Revolution Martyr Database, which use a different system for counting the dead, comes to the smaller number of 133,355. Regardless, the real number is likely to be significantly higher.

The image of Kurdi lying in the sand was so powerful that it appears it may even shake the world out of its inaction on a refugee crisis. However, thousands more children have died without changing anything, their death effectively becoming, at best, a statistic.

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