By Marie Jackson
Britain's most senior police officer wants children to be put on the child protection register they are if at risk of being lured into gangs by siblings.
Rickie and Danny Preddie were convicted of manslaughter
Sir Ian Blair says there is a need to protect these boys and girls from moving towards an "extremely dangerous lifestyle".
But just how common is it for gang members to want family members to join? And is it a case of younger ones being pushed in by big brother or drawn by the trappings and thrills of gang life?
Just last year, the Preddie brothers were found guilty of killing 10-year-old Damilola Taylor in south London.
Both were members of the Young Peckham Boys street gang, which terrorised the North Peckham Estate at the time of Damilola's death and had a string of convictions to their names.
With just a year between them, it is not known whether Rickie would have necessarily played a part in recruiting his younger brother Danny, or whether Danny had followed his lead.
Respect and status
Ann Tolaini works with young boys, mainly aged between 10 and 13, who are involved in or at risk of becoming involved in crime and gangs.
Among them, many are looking for a role model and an older sibling can meet that need, she says.
Furthermore, if that older person has respect and status within a community, ready cash and appears to be safe from trouble, that can appear attractive to young boys who do not always consider the consequences, she says.
"I don't know any brothers who are forcing younger brothers into gangs. They follow.
"Older brothers might not want them to join but that depends on the nature of the warmth within the family, how closely bonded they are and secrets within the family that will influence relationships," she says.
Her colleague, Guy Palmer, who works with her on the Bristol-based Right Track programme, said the closer in age, the more likely a brother is to follow, while the bigger the age gap, the greater the instinct to protect them.
Among many of the young boys he meets, they aspire to be like an older brother.
"Normally they are from families with quite a few children, often lone mums, where there is poverty.
"If they have a brother involved in drug dealing, and there's a lot of cash around - new trainers, scooters, cars, they see it as an easy way of getting it," he explained.
Sometimes the realities of life - perhaps a mother in need of financial support - can also sway them towards it, he says.
Their experience, though, is not borne out by Professor Gus John who has studied gang culture in Manchester and London and advised the Home Office on policy.
Police estimate there are at least 171 gangs across London
He says all his experience points towards peer groups as having gang membership pulling power, not siblings.
In fact, he says, there is a lot of evidence to suggest that within the same family, there may be a gang member with brothers or sisters who are "very straight, doing well at school and who have an abhorrence of activities of siblings".
"Take three young men from the same family - two may be doing extremely well at school and one may be in some pretty dreadful company," he explains.
"Typically what happens is the siblings try to protect one another from the effects of gangs.
"They tend to be more protective rather than getting them to join and younger siblings are not necessarily in the same peer group."
With those working at the frontline divided on the impact of family connections on gang membership, equally there seems to be a wider acceptance that it is a grey area.
The Metropolitan Police concedes gangs are an increasingly complex phenomenon.
Not only are they uniquely structured, but cultural differences can also influence the gang's formation and operation, a police report for the Metropolitan Police Authority said.
It also says while there are only an estimated three girl gangs among the 171 gangs across London, there is evidence that sisters and girlfriends of gang members are used to mind weapons.
Professor John said he was aware of spasmodic evidence of gun-minding.
"Some girls believe their brothers need a gun for their protection and think girls would be less obvious to the police," he said.
But Ms Tolaini said she did not believe sisters had quite the same influence.
"Brother to brother is more powerful - it's very much to do with the father figure."
So, as she and her team tried to establish other influences for boys at risk, she is also trying to find them more positive role models.