They stand out, if one looks closely, amid the massive human wave washing its way from the shores of the Aegean to the foot of the Bavarian Alps.
Here is a solemn-faced, solitary boy gazing about a jam-packed train station with preternatural wariness and calm. There, a little girl whose hair has not been brushed or combed for days. Just beyond, a group of teens clustered around the GPS on someone's smartphone, intently debating travel strategy — all with no adult in sight.
In the parlance of aid groups and governments, they are "unaccompanied minors," children younger than 18 who are making the perilous thousand-mile trek across half of Europe without a parent present — sometimes by accident, sometimes by deliberate choice, sometimes by a wrenching calculus of long-term gain for the family as a whole.
Although most very young children traveling without their parents are with a guardian figure of some kind, the presence of young refugees separated from their parents among the masses seeking haven in Europe is reminiscent of the flood of mostly Central American children traveling by themselves to the United States.
Although they make up only a small portion of the tens of thousands of migrants and refugees currently traversing Europe — between 4% and 7%, by the estimates of various international organizations — these youngsters pose a particular challenge for those who are trying to assist victims of war and persecution in finding refuge.
And in these overburdened days, their journeys come at a point when the resources of nations and aid groups are stretched to the breaking point, and safe haven is growing harder to find.
Germany, which had thrown open its doors to asylum seekers for more than a week, is implementing border controls that are preventing some from reaching the most coveted Northern European destinations — though the move is described as temporary, and German officials suggested Monday that they expect to take in as many as 1 million migrants this year, up from the 800,000 previously forecast.
Mazen Hassoun, a 16-year-old Syrian boy, arrived in Berlin this month from the town of Mansurah, near the city of Raqqah, the capital of the self-declared caliphate of Islamic State, the militant group that has overrun large swaths of Syria and Iraq.
"My parents believed I had to get out of there before I was forced to fight for Daesh," he said, using an Arabic acronym for the group. "We didn't have the money to bring the whole family, so it was decided that I would make the journey."
Many of the youngsters are silent and traumatized when they arrive, but remarkably quickly, they begin to reclaim their equilibrium — or appear to. On a recent day at a center in Munich run by a group known as HPKJ, both the lunchroom and a game room were filled with boisterous chatter — some in German, some in the children's native languages, including Pashto, Arabic and Somali.
"They become children again," said administrator Jutta Stiehler. "But at night, the ghosts come back." That is when the children's frightening memories sometimes manifest themselves in the form of nightmares and bed-wetting, she said.
Rimas, a 9-year-old Syrian girl who recently arrived at a refugee camp on Berlin's outskirts, sometimes cried for her mother during the long overland journey through Greece, Macedonia, Hungary and Austria, her uncle recounted.
The uncle, who was shepherding her and a 10-year-old nephew from Damascus at their parents' request, said that the sound of her nighttime sobs sometimes broke his heart — but that there was something he dreaded even more.
"The worst were the times when I could tell that the two of them, she and her cousin Mahmoud, they were too frightened even to cry," said designer Abdel Rahman Koweifi, 36, who agreed to take one child belonging to each of his two brothers on the long journey. He left his own wife and child behind in the care of his kin and hopes to send for them soon.
Despite some terrifying moments — their rubber raft overturned after setting out from Turkey, but close enough to shore that they were rescued — he managed to stay in touch with family along the way, updating the anxious parents on their progress.
The close-knit Koweifi clan had agreed that with the limited funds they had available to pool, sending the two children to travel in their uncle's care might ultimately give all three families a chance at securing a foothold in Europe. The journey cost a total of $4,500 for the three of them, Koweifi said. It's a choice many of those weathering Syria's seemingly unending civil war are making.
Aid workers say that youngsters who travel without their parents often feel intense pressure under the weight of a family's hopes — either that they will be able to secure work on arrival and send back money, or that a successful asylum application can pave the way for other family members to join them. In the course of the journey, unprotected youngsters are vulnerable to perils such as sexual assault and robbery, or worse.
"There's a whole range of concerns with relation to their safety in transit," said Michael Bochenek, a senior counsel on children's rights with Human Rights Watch in London. "Desperate people do what they have to do to make these kinds of journeys."
About four-fifths of the unaccompanied minors are boys, according to aid groups, and cultural norms tend to dictate their reasons for undertaking the voyage without their parents.
Families from Eritrea, Somalia and Afghanistan — all part of the current migrant wave — are more likely to hope that the lone teens can find work and send money home, regardless of whether relatives can join them. Among Syrians, who are thought to make up the largest group among the mostly unregistered exodus working its way through Europe, the object is usually family reunion in Europe.
Boys of 15, 16 or 17 who have made the trek in the company of other teens or an older hometown friend in many cases appear eager to assume an adult role. They boast of surviving a boat capsizing, scrambling through a gap in a border fence, breaking out of a transit camp. But ask them about resuming their high-school studies, and many look puzzled.
In the months before the current migration wave crested, places in group homes could usually be found for solitary teens. In Munich, Germany's gateway city for voyagers from the south and east, all 90 available places — half for boys, half for girls — are filled in HPKJ's home for kids younger than 16. There is a wait list at this facility and at other group homes in the city for unaccompanied minors, aid workers said.
In Berlin, Koweifi was happy that he had been allowed to remain with his two young charges at the camp in Karlshorst, the city's largest. Some of the women in the group of about 30 friends and relatives with whom he traveled had taken a maternal interest in Rimas, but she still misses her mother. The children are able to call their parents or communicate with them using WhatsApp at least once a day.
Their asylum paperwork has begun, though Koweifi expects it will take weeks or months before they know whether they will be allowed to stay in Germany. Of all the national groups currently on the move, Syrians have perhaps the best prospects for being granted asylum.
He recalled the tearful goodbyes in Damascus, the Syrian capital, when he swore to his brothers that he would guard their children's lives with his own.
"I said that if one of them were to die, it would be like my own death, but much, much worse," he said. "I look at them, and it is hard to believe we are safe. And perhaps we will all be together again — maybe not so soon, but someday."
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