Freetown, Sierra Leone - Aminatta stands in a narrow mud alley outside her house and rocks her brother's newborn baby from side to side. Her five-year-old son Thomas hovers nearby, trying to scribble on a mud wall with a broken pen. After a while, he totters over and tugs at his mother's skirt. He starts wiggling outstretched fingers while jerking his hips from side to side.

His mother roars with laughter. "He loves to bluff [show off]," she explains in Krio, the English-based Creole spoken here.

As mother and son play, Aminatta looks down, ashamed, as she recalls how she had once taken Thomas to the countryside and left him to die under a giant cotton tree.

Thomas has Down's syndrome, a condition that is rarely diagnosed in Sierra Leone and widely perceived to be the result of demonic powers. Boys and girls such as Thomas are commonly denounced as "devil children" who bring bad luck on their families and should be made to disappear with a ritual of black magic.

Aminatta says that as soon as her community saw that Thomas was not normal, they started urging her to carry out the ritual.

"No one realised for a while," she says. "He seemed OK at the start. He was born a triplet, and his two sisters died when they were one week old, but he was bigger and stronger than them. It was as he grew that I saw that his body was weak."

At six months, he was unable to lift his head or sit up, and his tongue would often loll from his mouth. This frightened the community, who started giving him names such as "jellyfish" and "devil boy".

"When I wanted to go to the market, I would ask a neighbour to watch Thomas, but everyone would refuse - they were all afraid of him", she says.

"It was very difficult. My husband died when I was pregnant, and I had nobody to help me with the child. Even my mother and sisters were telling me that Thomas was a devil. They used to try and beat the evil spirits out of him," Aminatta remembers.

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Succumbing to pressure

For a year Aminatta ignored the taunts, refusing to believe that Thomas was a "devil boy". But eventually, worn down with exhaustion, she started to question herself.

"I had never seen a devil boy. How was I to know how one looked?" she says.

"People were telling me every day that he was possessed and they said that it was because of him my other two daughters had died. Even my mother wanted me to do the ceremony. I was so tired, and they had provoked me so much that when he was a year and two months old, I finally agreed to do the magic which would return him to the devil."

Aminatta lives in Kroo Bay - a sprawling shantytown in the west of Freetown. As black magic tends to happen outside the city, she decided to travel back to the village where she was born to perform the ritual.

She packed a bag for herself and Thomas and took a bumpy four-hour bus ride to the northern district of Kambia where her mother and sister were still living.

Aminatta, ashamed, lowers her voice and lets her eyes wander to the floor. "I spoke to the sorcerer in the village, and he told me that he could do the ritual. I just had to prepare a white satin gown made to fit Thomas and buy six eggs and some flour."

A common myth in the area claims that during a black magic ritual, so-called devil children will turn into snakes and slither away, never to be seen again. This is what Aminatta was expecting when the sorcerer came to her mother's house, she explains.

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"We put Thomas on the floor, dressed in the gown, and with a circle of eggs and flour around him.

"The man made some chants that I couldn't understand, and we watched Thomas, waiting for him to turn into a snake and eat the food we'd offered him. After two hours, nothing had happened, and the sorcerer said that it was because we hadn't done the ritual correctly. We weren't supposed to do it in a house; we should have taken him out to the bush and left him there. So we agreed to do it again, this time in the proper way," remembers Aminatta.

Some days later, Aminatta dressed Thomas again in the satin gown and headed out to the bush with a small party of people, including her mother and sister.

The same ritual took place, but this time, Thomas was put in a hole amid the giant roots of a cotton tree. Once the chanting was finished, Aminatta ran from the ceremony, crying, she says. "It was too painful to stand there, so I went back to my mother's house, sat in the kitchen and wept."

Some time later, her mother and sister appeared saying that the ceremony was over and Thomas had been left under the tree. The sorcerer had told them that after some time, a strong wind would blow and the boy would surely turn into a snake.

"I was extremely upset," says Aminatta, "I hated leaving him there. I tried to go back and take him, but my mother and sister restrained me."

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Reunion and help

After two hours Aminatta heard a shriek from her sister, who was sitting on the porch and ran outside to see what was happening.

Thomas, still dressed in white satin, was crawling towards the house laughing and gurgling. "I ran to pick him up and wiped my tears on my sleeve. I started laughing, too. I hugged him, and we laughed together."

Aminatta says that after the two failed ceremonies, her mother and sister finally conceded that her son was not a devil child, apologising to Thomas for what they'd put him through.

The two of them travelled back to Freetown and have been enrolled in a programme called Enable the Children, run by the charity World Hope, which teaches parents to nurture children with disabilities.

Abu Bangura, the pastoral support worker at the charity, says that Thomas has been making progress which is very encouraging for everyone. "He is practising the exercises we taught him and getting stronger. And most of the community seem to have finally accepted him."

His colleague, Jonathan Williams, explains that the mistreatment of children with Down's syndrome and other disabilities in Sierra Leone is not only a result of superstition but also of poverty - parents can simply not afford to spend extra money on children with extra needs.

"They are seen as a waste of energy and resources," he says. Indeed, in a country where most of the population survives on less than $2 a day, many families can't provide for disabled children, especially if they hold no promise of economic return in the future.

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Entrenched attitudes

It is not common to see children with Down's syndrome in Sierra Leone. Nurse Unisa Tarawallie works at Princess Christian Maternity Hospital, the biggest paediatric health facility in the country, and says few children with Down's syndrome come in.

"It seems that they prefer to stay at home, though we might see around two of them a month for the physiotherapy sessions that we run. Their parents never know what Down's syndrome is and usually have a story about the child being affected by a demon."

He adds that after being given a full scientific explanation of the condition, the parents are relieved and often come back to the hospital for more help.

It is a lack of information about Down's syndrome that puts children with the condition at risk. Black magic rituals such as the one which Thomas was subjected to are alarmingly common in Sierra Leone.

Executive secretary for the National Disability Commission, Lamin Kortequee, says that his organisation tries to inform communities about disabilities as well as prosecute those who discriminate against disabled people.

However, they have never put a witch doctor on trial for conducting a fatal ritual on a disabled person.

"We cannot prosecute because these things are not reported. They are seen as norms," Kortequee says.

"These attitudes are entrenched in society, and I think we can change them with advocacy, but it's not going to happen overnight."