The threshold for child protection intervention in the case of a woman who smothered her three disabled children was reached one year prior to their "unexpected" deaths, a serious case review found.
Tania Clarence, 43, has previously admitted the manslaughter by diminished responsibility of Olivia, four, and three-year-old twins Ben and Max at the family home in New Malden, south-west London, in April 2014.
The children suffered from the muscle-weakening condition multiple system atrophy type 2.
The review, commissioned by the Kingston Local Safeguarding Children Board (KLSC), covered a period of 42 months from the premature birth of the twins in July 2010.
It noted the diagnosis of the children meant a "huge emotional and practical adjustment" for Clarence and her husband Gary, an investment banker who worked long hours.
It became clear early that Clarence was "overwhelmed" with a large number of appointments and by the end of 2010, professionals began to identify she was possibly depressed.
In July 2011 Clarence requested the children be designated Do Not Resuscitate if the need for ongoing treatment arose, and expressed the family's view that "medically invasive treatment was cruel", the report stated.
She declined any offer of counselling despite her presentation - "her crying, her flatness and her avoidance of eye contact" - sparking concern from GPs.
But the report said at that point "there was nothing in the mother's behaviour that suggested she would need to be detained in a hospital in the interests of her own health or safety, or with a view to the protection of others".
In February 2013, professionals began referring to "neglect and emotional abuse" with regard to Olivia, including comments from Clarence that "she wouldn't be around to see (the child's) future attendance at university".
The report noted: "It was queried whether this was a threat to commit suicide".
In the subsequent six-month period, the concerns escalated. Clarence's "non-compliance and interference with medical equipment" was noted when Olivia was admitted to hospital between May and June 2013.
The report said that, in July, consideration was given to the involvement of the police but according to the social care records, St George's Hospital "did not think that would be helpful".
It said: "The concerns during this period, in the view of the authors, reached the threshold for child protection intervention, but this did not happen, despite references to legal intervention."
The independent authors added: "The need for a child protection enquiry should have been considered, to establish the basis of the various allegations made and then retracted".
KLSC Board chairwoman Deborah Lightfoot said: "While the review states that all of the deaths were not predictable nor preventable, it has found that there are learning points for practitioners involved."
It has made 11 findings and handed down 14 recommendations.
But the review stated: "There is no certainty that any of the findings would have made any difference to the tragic outcomes in this case."
While those circumstances were "unusual and challenging", the broader issues they raised were important, according to Spinal Muscular Atrophy Support UK.
Spokesman Martyn Sibley welcomed the recommendation that all parents of children with the condition be offered information and support at diagnosis as routine.
He said: "We are aware that this happens very well in some areas but it is not consistent across the country."
The family was involved with various arms of the health care system as it moved from Merton to Wandsworth and later Kingston.
The review examined the role of staff at Great Ormond Street Hospital, St George's University Hospital, Royal Brompton and Harefield Hospitals, and Kingston Hospital along with NHS GP services.