His co-workers towering over him, Mohamed stands at the machine, its buttons and levers at chest level, and quickly makes three coffees, his arm stretched high to reach the coffee press.

A refugee from a village outside Syria’s capital, Damascus, Mohamed is an old hand at the café – although he’s only 13, he’s already been working there for a year and bears an extraordinary responsibility as his family’s sole breadwinner. He earns $US133 ($148) per month.

A combination of his father’s heart condition and his struggle to find work in Lebanon has left his family with few options to survive.

“Of course we would prefer him to go to school… Mohamed is very young and we should not have to depend on him,” his mother Houda says inside the tiny, neat two-room structure they call home.

“We are in an impossible situation.”

In the Damascus countryside Houda, her husband Waleed and their five children had a large, five-bedroom house and a car, and the family lived well on the income from Waleed’s job in tourism.

But as Syria’s brutal conflict dragged on, the tourism industry dried up. Then Waleed was arrested by the Syrian regime, jailed and tortured for four months.

His health was so precarious by the time he was released the family had no other option but to flee to Lebanon.

“Before we left we were without water and electricity,” Houda says. “The rockets fell on a daily basis and the food was running out.”

Waleed’s brother, who stayed behind, says his family is starving, with little more than weeds to eat.

“We built up our family and our home over many years, but we have lost everything, I had to sell our car to come here and our house was half destroyed by a rocket,” Waleed says.

“Now we have no resources left and no way of rebuilding our lives and we are dependent on a 13-year-old boy,” he says, looking at his son with a mix of love and sadness.

Mohamed is matter-of-fact about is job at the café.

“I get up early and I work an ordinary day,” he says. “If I don’t work who is going to provide for the family?”

With his mother urging him to say how he feels about school, he admits: “I miss going to school, especially when I see the other children going to school - I come home and tell my mother and father that I want to go to school… I hope to become an engineer.”

Mohamed is not alone. Syrian children are working throughout Lebanon, on farms, in shops, on the streets, in factories and on building sites - anywhere they can earn money to help their families afford food, shelter and medication.

Along with local Lebanese aid groups, CARE International is providing support to Syrian refugees in the Chouf Mountains and in the Tripoli region in the north of Lebanon, distributing cash, heaters, fuel vouchers, weather-proofing kits and floor mats as well as sanitation and baby packages.

In its assessment of the needs of those in the Chouf Mountains it found most families were deeply worried by the lack of prospects for their children – with 66 per cent not attending school, the prospect that their children would be illiterate was a “profound fear among parents”.

Lebanon is home to more Syrian refugees than any other country. Along with its own population of 4.4 million, there are more than 860,000 Syrians officially registered as refugees, although the Lebanese government estimates the number is much higher and probably more than one million.

Unlike Jordan and Turkey, Lebanon has not established any refugee camps, so the majority of refugees live in unfinished houses, schools, mosques, disused buildings or informal tent settlements, all placing huge pressure on Lebanon’s already struggling water, sewage and electricity infrastructure.

In many cases it is only through the generosity of Lebanese land and property owners that the Syrian refugees survive.

In Mohamed’s family’s case, the café owner is providing their small, two-room flat for free, while for others, landowners have paid for the construction of shelters as well as sanitation blocks for the refugees forced to live on their land.

It is a catastrophe of such dimensions that the United Nations High Commissioner for Refugees is warning there will be more than four million Syrian refugees by the end of 2014, overtaking Afghans as the world’s largest refugee population.

Since the war in Syria began nearly three years ago, 2.5 million people – half of those children – have fled, mostly to Lebanon, Jordan and Turkey, the UNHCR says. (Afghan refugees now number 2.6 million).

More than 6.5 million are internally displaced in Syria and more than 9.3 million are in need of urgent assistance, the UNHCR says.

Local groups say more than 125,000 people have died (the British-based Syrian Observatory for Human Rights puts the figure at more than 140,000), while many more have been horrifically injured and whole towns, along with crucial infrastructure, destroyed.

In Chimme, my visit with Mohamed’s family is coming to an end, and he is anxiously waiting outside the front door.

“I have to go back to work. I have been gone too long,” he says as he walks alone up the narrow, winding road to Chimme’s main street and to the café that has replaced his classroom.