How can social services intervene to support families where the issue is neglect rather than abuse or harm?
For 12 years, Karen Matthews, mother of seven, wobbled precariously along the line separating adequate parenting and child neglect.
At times her dismal failure to keep those four of her children who lived with her clean, secure and healthy, coupled with her often inappropriate choice of male partner - would bring the family under the spotlight of social services. One or other of her children might be put on the child protection register.
And then, with the support of social workers, would come a period of co-operation and relative stability. The children would attend school or nursery regularly, the chaos would abate, and the children would come off the register, the social workers recede from view. And then it would all start going wrong again.
Until the extraordinary abduction of her daughter Shannon this pattern of incipient, low-level neglect continued, never quite disappearing, but never serious enough to warrant taking the children into care. Indeed there was evidence, today's serious case review report concluded, of "a mutually loving relationship" between Matthews and her offspring - although it adds pointedly that she "was not aways able to translate this into the practical requirement of good parenting".
This kind of undisciplined, incompetent parenting is far from unusual, the review's author, Dr Carole Smith, told a press conference today. "We are looking at a fairly common problem".
Cabinet Office research estimates there are about 140,000 such families in Britain, defined as "experiencing multiple disadvantage." About 250,000 parents have a learning disability (Karen Matthews was diagnosed as having "borderline learning disability") while 154,000 children live with parents with a serious and enduring mental health problem. All need social support.