Opportunities to intervene before a 16-month-old girl was killed by her father "were missed" by social services and other agencies, an inquiry has found.
Amy Howson, from Doncaster, South Yorkshire, had her spine snapped by her father James in December 2007.
A serious case review found the town's children's services team failed to take proper action to safeguard the girl, who also was beaten several times.
It identified "three key missed opportunities" to intervene.
Howson, of Nelson Road, Doncaster, was jailed for life with a minimum term of 22 years after being convicted of Amy's murder.
Her mother Tina Hunt was given a 12-month sentence suspended for two years after admitting she allowed the death of a child and child cruelty.
The serious case review referred to Amy as Child B.
In its conclusion, it said: "The murder of Child B by her father... was not predictable given the information and knowledge held on him and other family members by agencies.
The 'missed opportunities'
By Doncaster Community and Schools Social Worker Service after police were involved in a domestic violence incident involving the family in January 2007.
By the Youth Inclusion Support Service and the other child's school in May 2007 when neither agency "properly recognised, heard and acted on the boy's concerns about (the father's) aggressive behaviour".
By the Doncaster Primary Care Trust Health Visiting Service in November 2007 which "failed to assess any risks to Child B and (the other child) in the context of the parent's disengagement with the service".
"However, there was sufficient information and knowledge on family members, including (the father), held by individual agencies to conclude that, on balance, both Child B and (another child) were at risk of significant harm from him.
"Some agencies within the Doncaster multi-agency child protection system failed to follow basic safeguarding procedures and did not take proper and effective action to safeguard and promote the welfare of Child B and (the other child)."
The review also concluded an "inter-agency working and communications were deficient".
It identified "three key missed opportunities for agencies to intervene with a proper assessment and subsequent child protection plan".
Another report highlighted failings in the case of 11-week-old Alfie Goddard, who was also murdered by his father in the Toll Bar area of Doncaster.
Alfie died of head injuries at Sheffield Children's Hospital in May 2008.
His father Craig Goddard dropped Alfie down the stairs in a "moment of anger" when the boy would not settle.
Goddard was jailed for life and told he would serve at least 11 years in prison after admitting murder.
Howson and Goddard have both been given life sentences
The report said "agencies did not appropriately recognise that adult issues of anger, mental health problems, substance use and domestic violence could be risk factors for children and neither did they appropriately assess the needs of the children and provide services accordingly".
It said said some agencies, including South Yorkshire Police, "had a high level of involvement with the family over many months and some individuals showed great persistence and commitment to the family".
But it said those agencies generally acted in isolation, with inter-agency working and communication "being largely inadequate".
Amy and Alfie are two of seven children who have been the subject of serious case reviews in Doncaster since 2004.
The government ordered a takeover of the town's children's services department in March.
The council's interim director of children's services, Gareth Williams, said: "Although there continue to be serious problems in appointing permanent staff to the duty and assessment team, plans are in place and being delivered to achieve a service that is operationally effective and resourced by experienced staff
"A multi-agency training programme is now in place and being delivered to ensure that everyone providing services for children are meeting their responsibilities for common assessment."