British charity Street Child is helping teenage mothers like Princess to survive in one of Liberia's largest slums

In a country where most exist below the poverty line, Princess' tale isn't unique – but to Street Child, she's an individual, not a statistic

Another chance: Princess with her daughter, Angie (Gabriella Jozwiak)

Princess Mayers sits on a wooden bench under the shade of a corrugated zinc roof in one of Liberia's largest slums. She faces a narrow beach, but the yellow sands are no paradise.

West Point, in the capital, Monrovia, is famed for having only four public toilets for its 70,000 residents. The shoreline is awash with human faeces, waste and the infectious diseases they carry.

But Princess, 16, has called the beach home for two years. She is not from West Point and once lived in Benson Street in the city centre, a bustling avenue that begins at a tree chattering with fruit bats outside the US embassy and ends at the wide Mesurado river. Her home was meagre, but Princess insists that it was "a proper house with concrete walls". Her father abandoned the family and her mother sold dried chillies to pay the rent and feed her three children. But school fees were unaffordable.

Princess's life fell apart at 14 years old when her mother caught yellow fever.

"She was sick Monday and Tuesday. On Wednesday, she died," Princess says, in a flat voice. "We couldn't afford medicine. The landlord gave us our notice. My grandmother lives nearby, so she took us in. But she barely has any money. She sells soft drinks in the road."

Liberia is still recovering from the 14-year civil war that killed 250,000 people. About 64 per cent of its population lives below the poverty line. Children can be a family's means of survival, with almost a fifth of six- to 17-year-olds working to fund their parents and siblings. Princess, despite being illiterate, set out to support her siblings. "I braided people's hair; did whatever odd jobs I could," she says.

While she is not accustomed to being the centre of attention, Princess agreed to tell her story in the hope that it might help other girls like her. But she races through her biographical details, pressing her fingers together anxiously as she speaks and twisting her gnarled feet out of her flip flops into the rubbish-strewn sand.

She repeatedly looks to her social worker for reassurance. Musu Rogers, who works for the British charity Street Child of Liberia (SCoL), sits next to her in the shack. Musu found Princess on this beach a month ago.

"I came here because I met a boy called Abraham," Princess continues. "He was older than me and we started dating. He didn't go to school or have a job. Like me, he was just trying to get by." Abraham brought Princess to West Point to buy drugs.

"The first time I smoked marijuana I felt sleepy and slept really well," she says. "I smoked more and eventually tried cocaine."

Another chance: Princess with her daughter, Angie (Gabriella Jozwiak)

Too ashamed to return to her grandmother, Princess stayed. The couple slept on the filthy beach under an up-turned, dugout canoe – a hellish version of a sex-on-the-beach fantasy.

Their relationship quickly descended into drug addiction and physical abuse.

"Drugs made Abraham aggressive – he beat me many times," recalls Princess, pointing to a scar by her left eye.

She glances at some men in the shack. They are smoking, jeering and sucking their teeth. Their sleepy, yellowed eyes betray that they are either high or coming down. There are hundreds of men like them in West Point, hardened by living in extreme poverty, who turn to drugs such as heroin to numb the pain.

Princess isn't like them – she sits, softly vulnerable; intimidated. She is still a child. It is not easy listening to what she reveals next. "We never had enough money, so I began working as a prostitute," she says in a whisper. "I did it in the daytime when Abraham was away and never told him. I would go to the town centre. The men were older – they picked me up on motorbikes and took me to an alley. I'd get it over with as quickly as possible."

Princess leans her thin shoulders forward, exposing stretch marks above her breasts.

"I realised I was pregnant," she tells me. She places her hand on her belly, still rounded from the child born six months ago. She insists that it was Abraham's because she used condoms with clients.

Friends advised Princess to have a backstreet abortion. "I didn't want to do it because I didn't want to die," she says. Three years ago, her 14-year-old friend Fatu was killed by a "quack" abortion. "Despite my suffering, I decided to keep my baby," she says. "I thought the child would be my future."

Princess is startled when the shack's owner, Mohamed Carew, shouts at one of the men. He is minding the entrance, conspicuous because of his gleaming gold watch and chain. To have bling like this in West Point, the wearer must have people's respect. And "Gaddafi", as the locals call him, certainly has that. He earned the name because of his bravery in confronting detractors, one local tells me.

The name seems unfair because Gaddafi has become a hero for local youths. Last year, three of his children left home to become involved in West Point's destructive street culture but, with SCoL's help, they returned. Since then, Gaddafi has worked as a volunteer for the charity, turning his shack into a contact centre for children and their parents. In the afternoons, SCoL educators teach here. Above the door, Gaddafi has painted a new name: The Old School Club.

Princess returns to telling me about her pregnancy. She had ruled out asking her grandmother for help. "She didn't have the means," she explains. "It would have put more pressure on her finances and added to my siblings' suffering." To save money for the birth, Princess continued sex work while pregnant. She hid the earnings with a friend to prevent Abraham blowing them on drugs.

When she recalls going into labour, Princess almost shrieks in memory of the pain. It sets off her cough – deep and rasping with catarrh – she has developed from sleeping rough.

"I'd managed to save 2,000 Liberian Dollars (£14)," she says, through the splutters. "I couldn't afford to go to a clinic, so I asked my friend to help me reach the house of a nurse in West Point. We walked there and the nurse accepted 800LD (£5.70)."

Princess and her daughter with Beatrice Johnson, a relative who is now helping to look after Angie (Gabriella Jozwiak)

The nurse's house was dark inside, made from the same corrugated zinc as the rest of the slum. But it had a plaster floor and Princess relished the relative luxury of lying on a mat with a pillow under her head. "After an hour of intense pain, I gave birth to a girl," she says. "I was very afraid, but when she put my daughter into my arms I felt happy. She was pretty. I called her Angie, because she was like an angel." Princess finally smiles. It changes her face completely, lifting the lines from her brow.

But it soon fades as she explains that she then had to raise her daughter under the canoe. In the daytime, equatorial Monrovia sizzles. But at night, chilled Atlantic winds made Princess and Angie shiver. Rains kept the sand damp.

"Angie was not well. She was quiet and hardly cried," recalls Princess. "I cleaned people's clothes to raise money for a bowl of rice, but eventually went back to prostitution."

The situation for Princess grew worse. "Abraham was beating me regularly," she says. "One day when Angie was still tiny, he tore her out of my arms with one hand, while he punched me with the other." As she says this, she raises a clenched fist. "He threw Angie onto the sand and she hit her head on a stick. I screamed, but I couldn't reach her because he was attacking me. I was so scared. Eventually, someone came to help and took Abraham to the police."

Afterwards, Abraham disappeared. It was then that Gaddafi spotted Princess, gave her food and called Musu Rogers for help. Musu began visiting the pair every day. "The way Musu was reminded me of my mother," says Princess. "She was the first person who had taken time to listen to me." But Musu had to act quickly. "The child looked sickly," she tells me. "Her skin was dropping off."

She organised funds to take Angie to the doctor, who discovered that the baby had tongue-tie, a problem that restricts movement of the tongue. The charity paid for an operation to fix it. "Now she's OK – she can cry now," says Musu, adding that her priority was to get the pair off the beach.

Princess wants to show me her baby, so we leave the crush of shacks to visit the home where Angie now lives. We take motorbikes through streets packed with snack stalls and arrive at a side of West Point where, although still poor, the atmosphere is less tense.

After weeks of searching, Musu found a distant relative who agreed to care for Angie. Beatrice Johnson's house is almost directly under an electricity pylon (on which the neighbours have hung their washing), but it has brick walls and a solid roof that protect them from the wind and rain. When we arrive, Beatrice is laundering bright fabrics and gives us an easy smile. She has a steady job as a street cleaner for the Monrovia city corporation, for which she has earned her community's respect.

Princess lifts Angie off the floor, where she is rolling near Beatrice's feet. The scar from her father's attack is visible near Angie's eye; a match for her mother's. Angie is little for her age: quiet and still sick. "But she's trying small small, she's coming on small small," says Princess in a Liberian turn of phrase. Although she was sad to hand over Angie to Beatrice, Princess is relieved. "I can visit every few days," she says.

SCoL is funding Angie's care and wants Beatrice to extend her home to accommodate Princess as well. To do this, the charity has provided a small business grant and training to help Beatrice develop a sustainable, long-term income for her new family. Michael John Bull, the charity's Liberia director, is also trying to fund Princess's rehabilitation and return to school. She is still taking drugs and working as a prostitute to finance her siblings' upkeep.

No figures exist on the number of girls like Princess, but Bull estimates that four in 10 girls living or working on West Point's streets are in a similar or worse situation. "Families are sometimes pushing their girls to the streets as a means of feeding homes," he explains. "Sometimes the girls themselves are unwilling to accept there is another way."

Princess, however, says that she is ready to change. "I hope to learn to read and write," she says, fondling Angie's feet. "I want to become a lawyer so I can save my friends on the street from their troubles."

As we prepare to depart, Princess assures us that things are getting better. "My baby is my future and I'm happy I have her." We leave her sitting on a new bench, leaning against a green-painted wall with Angie and her dreams.

Donations to Street Child are matched pound for pound by the UK Government until 17 June. To help the charity reach hundreds more girls like Princess, visit street-child.co.uk