Back in March - as the makeshift Idomeni camp on Greece's border with Macedonia made headlines - Babar Baloch, the UNHCR's spokesman for Central Europe, witnessed something that has become surprisingly common for aid workers.

"There were 12 children from 10 to 16 years of age from different backgrounds - Syrian, Pakistani, Afghan - that were being kept in a police lockup because there wasn't enough space for them," Baloch told DW.

"They weren't sure what was happening to them," Baloch added.

Children made up an estimated 40 percent of the 10,000 people at Idomeni - a place that Baloch described as "not fit for human beings."

Though shockingly high, that ratio is below the global average: According to a UNICEF report released on Wednesday, roughly half of the world's more than 21 million refugees are younger than 18.

In all, UNICEF puts the number of forcibly displaced children at roughly 28 million worldwide, including an estimated 1 million minors who have applied for asylum and 17 million people internally displaced in countries across the globe.

Lost and alone

Seventy percent of refugees who entered the EU as minors in 2015 came from Syria, Afghanistan and Iraq, according to UNICEF. And, like the youths whom Baloch saw in the Idomeni lockup in March, they experience disorientation and worry.

"The trends we have seen are either that children don't have parents or the parents have died," Baloch said. "Or they actually been asked by the parents to start this journey because they fear for their children's safety in many conflict zones." And families can get separated along the way.

The youngest unaccompanied child whom Baloch has encountered was a 5- or 6-year-old boy from Afghanistan. His parents had drowned in the Aegean crossing from Turkey to Greece. Last year, Baloch met the boy at the Keleti train station in Budapest, where the child had arrived with fellow Afghans who watched over him after his parents died. The goal was to continue to Germany, where an uncle of the boy's lived.

In addition to facing the same traumas as adult refugees, unaccompanied children are at risk for exploitation by human traffickers and employers.

"It's a very tough life for them," Baloch said.

International law

Under the UN Convention on the Rights of the Child - one of the most widely ratified treaties since its implementation in 1989 - nations must first and foremost consider the best interest of children when determining custody and asylum status.

In accordance with the UN convention, the EU's Dublin III Regulation - which determines which member state is responsible for processing a person's asylum application - further ensures qualified legal representation for minors and helps expedite the reunification of unaccompanied children with relatives. It also guarantees minors the right to express their views on their asylum applications.

With the arrival of more than a million refugees in the European Union last year, many of the bloc's member states are struggling to accommodate the needs of children and teenagers - not only in terms of integration, but also in terms of custody.

An estimated two-thirds of refugees younger than 18 have sought safe haven in Germany. By the end of 2015, the country had received more first-time asylum applications than any other country (441,899). One-third of these, or roughly 117,000, were filed for minors. And, of those, an estimated 14,000 were unaccompanied.

According to Germany's Interior Ministry, 8,000 refugee minors went missing in 2015. More than 500 of them were children younger than 14. German officials believe that in some cases minors have reunited with relatives who have failed to report them as "found."

'Children are children'

The European Union continues to endure heated public debate over the humanitarian crisis, and the number of attacks on refugees has risen in multiple countries. Nevertheless, Baboch said he had observed great empathy for unaccompanied children and refugee families in such countries as Greece, Croatia, Bulgaria and Hungary.

Baloch said, however, that some politicians, including those leading the government in Hungary, where he is based, "don't want the general public to see refugee children as children."

Because these young refugees are the most vulnerable and because they will one day be full-fledged members of society, "we need to try to focus on the issue of 'children are children,'" Baloch said, adding that EU members must create more effective mechanisms to protect them: "They need to have a childhood."

More than that, Europe needs to be reminded of the larger context. There are 21 million refugees across the globe. "Europe is thinking that every refugee in the world is coming to Europe," Balcoh said. "That's not the case. Nine of 10 refugees are still being hosted in the world's poorest countries."

"That's the reality on the ground," Baloch said.