A few yards from where Kayser Osman was stabbed to death, scores of new homes are going up in the Church End estate, neat little two-storey affairs with gardens. Round the corner two bobbies are patrolling the estate, one black, one white. For a moment it is an image of peace and security. But the appearance is deceptive. This is one of the poorest, most crime-ridden parts of London and, according to many people who have to live here, it is no surprise 15-year-old Kayser was killed by a 14-year-old boy - with a knife brought to him by his cousin aged 11.