Ricky and Danny Preddie grew up in a broken home on a South London estate and owed loyalty only to each other and their gang of child thugs, the Young Peckham Boys.

Ricky was 13 and Danny 12 when they attacked the ten-year-old Nigerian schoolboy as he made his way home from Peckham library on a cold, wet evening in November 2000.

The Preddie brothers were already veterans of the courts. “They were the scum of the Earth,” a policeman who worked in Peckham at the time said. “Whenever there was a robbery, one or other of the Preddies was involved.”

Danny Preddie had bullied Damilola and is said to have coveted his silver jacket. Ricky is believed to be the gang member who stabbed their victim with a broken beer bottle. “Juking” was a punishment administered to anyone who showed the Young Peckham Boys disrespect or resisted their demands for mobile phones, baseball caps, trainers and cash. It was intended to wound, but in the attack on Damilola the glass sliced an artery. He bled to death in a stairwell.

Often when members of the gang were brought before the courts they were too young to be jailed or the case collapsed because witnesses had been threatened.

The Preddie brothers were born within 11 months of each other to Marion Johnson, a Londoner from Dulwich, and Alfred Preddie, originally from Jamaica, who registered his occupation as shop owner on the birth certificates.

Miss Johnson and Mr Preddie were unmarried and their relationship foundered when the boys were young. Miss Johnson, a former post office worker and cleaner, still lives in the shabby second-floor maisonette where the boys were brought up. She watched part of their Old Bailey trial from the public gallery.

At one stage Mr Preddie was under investigation by Operation Trident, the Scotland Yard unit set up to combat black-on-black gun and drug crime. Detectives emphasise that he was never charged and suspected only of being a minor player.

The boys kept in touch with their father and, when he died two years ago, Ricky was allowed out of custody to attend his funeral.

For the early part of their lives the brothers caused few problems. Their maternal grandmother was an influence for good in their upbringing. But by the age of 11 they were regularly getting into trouble and were sent to Bredinghurst special school in Peckham Rye, an institution that caters for pupils with “severe emotional and behavioural difficulties”.

Bredinghurst was a last-chance saloon and the Preddies failed to take the opportunity. Danny was sent to the Hollies children’s home in Bermondsey, but repeatedly slipped out to join friends on the streets.

On the day of Damilola’s death, Danny had been in court for breaking a bail curfew. He was facing five charges, three of them for assault.

Ricky was living at home but was also running wild. He was facing theft charges, was under a supervision order and had attended the Orchard Lodge assessment centre in Penge, southeast London. Sometimes he would turn up at his grandmother’s home for his tea and occasionally stay at the centre for basketball practice. But he was also frequently absent and out on the streets with the Young Peckham Boys.

One of the most disturbing factors of the Damilola case is that the life of the Preddie brothers is far from unusual. Raiding a dozen homes on the North Peckham estate in the aftermath of Damilola’s death, police found only one household where a father was living permanently with his family.

Camila Batmanghelidjh, who founded the South London charity Kids Company, said that many of the troubled youngsters she dealt with were “suicidal kids who don’t care what happens to them. Because of this they are very powerful.”

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