Peter H Toe, a slow-moving 78-year-old with rheumy eyes and deep frown lines, is considering the daily dilemma he faces finding enough food for the 52 children in his care. "They say if you can feed a chicken until it's not hungry any more you can feed a child," he laughs scornfully as he pretends to peck in the dust like a scavenging bird. "But everyone knows chickens and children are always hungry."

The owner of the Ktoe Comfort Orphanage, situated just outside the Liberian capital, Monrovia, stares across the sun-scorched yard where, next to an evil-smelling lavatory block, the children are hard at study. The classroom roofs blew off in a recent storm and only thin plastic sheeting shields the young scholars from the elements. Unless it is fixed, lessons will be impossible in the next rainy season.

Mr Toe and his wife Comfort, now lying virtually paralysed by a stroke in a bed behind us, are by all accounts good people struggling to cope with an impossible situation. They led the children to safety here during Liberia's 14-year civil war, hiding in the bush and begging for food.

Mr Toe remains fiercely protective of his young charges. "These children aren't going anywhere unless I am certain they will not suffer," he insists.

A plaque on the wall reveals the dormitories were erected with the assistance of the 92nd Irish Battalion. Though sturdy on the outside, they offer an unprepossessing view of life for Liberia's army of orphans.

Inside, 52 children bed down each night in two dingy rooms, with nothing but a flimsy mattress or a wooden palette between them and the floor. There is no electricity and in the steamy tropical nights, jammed full of sleeping bodies, the rooms are sweltering.

Most upsettingly there are no photographs of loving, smiling families. These children have only each other. Yet these, it seems, are the lucky ones.

The long years of war destroyed Liberia's social fabric, ripping apart hundreds of thousands of families. Today there are nearly 5,000 children living in the country's orphanages, a figure that has more than doubled since the end of the civil war in 2003. But not all are without parents. Some estimates suggest as many as 70 per cent of the children have been abandoned by families unable to cope with another mouth to feed.

Save the Children, one of the three charities supported by this year's Independent Christmas Appeal, is working to keep Liberia's children in their homes. It is also seeking to improve orphanage conditions for those for whom there really is no alternative.

Ina Christensen has been inspecting orphanages since the war. As many as seven out of 10 can fail to meet the most basic standards at any one time. In the worst of them, children may be malnourished or sick. Last year a study by the United Nations found the owner of one institution ordered youngsters to "fast" for three days because there was no food.

The homes, sometimes little more than falling-down hovels, are often without running water or sanitation and there is an ever-present danger of sexual abuse when teenage girls are forced to sleep in the same room as mature boys.

It is commonplace for children's names to be changed, severing them from their past and stripping them of their identity. In extreme cases they are used as little more than bonded labourers, or worse.

"In one of the homes the proprietor was selling the girls for prostitution," says Ina, a child protection worker for Save the Children in Monrovia. "Neighbours said they saw men coming to the house and taking the girls away. We closed her down but she set up again in another county and we had to close her down again."

In a country as poor as Liberia, it seems there are those only too willing to exploit the most vulnerable youngsters for as little as the $6 to $10 a month the government pays orphanage owners to house each child.

Young people have become commodities, fuelling the rapid growth in orphanages. From just 10 before the war in 1990, there are now 106, with new ones emerging every month.

Too often though, payments designed to feed and clothe the children go towards the owner's costs.

Then there is the lure of overseas aid. Last year Save the Children intercepted 938 children being removed from a displaced person's camp in Monrovia. They were bound for an orphanage funded by a wealthy Liberian businessman living in the United States.

Another symptom of the orphan crisis is the soaring rate of overseas adoptions. The number of children entering the US where adopting couples pay $12,335 (6,250) to receive a child is up by 500 per cent since 2004 to 353 last year.

Liberia's entire social welfare budget in 2007 was just 350,000. Up to 10 times as many trained social workers are needed in Monrovia to make a difference, says Deputy Health Minister Joseph Geebro, who hopes to publish the draft of the country's first social welfare policy next May.

Victoria Thomas, 42, lost her husband in the war and now has 54 children at her orphanage. She says she receives just 170 from the government every three months for their upkeep.

Despite the paucity of their existence, there is a clear bond between "Ma" and her children. The sad truth, though, is that these teenagers are almost certain to spend the rest of their childhood in the orphanage.

Lillian, 14, appears to have given up all hope of being reunited with her family. "Sometimes I see parents with their children and I feel very sad," she sighed. "But then we compare our situation with those poor families who have to look after children and we think maybe it is better for us to be where we are."

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