Bronson Battersby’s body was found in his Pudsey Bear pyjamas around two weeks after he was last seen alive on Boxing Day.
Social services had rung dad Kenneth Battersby, 60, the next day to plan a home visit for January 2, but he did not answer, having potentially already died.
That left the toddler alone in the dark with no food and water at the home in Skegness, Lincs, before he too died.
After the failed call the social worker contacted police and then visited two days later, said Lincolnshire County Council.
When there was no answer at the door the social worker again contacted police, but it was five days before the bodies were found on January 9 after the social worker got access from the landlord, the council claimed.
A review has been launched by the council after tests reportedly found Bronson, who was under children’s services care, had died of dehydration and starvation. The council said: “The social worker is devastated, we all are.”
The social worker has not been suspended but has taken time off following the incident.
Lincolnshire Police said the actions of all organisations involved will be examined as it referred itself to the Independent Office for Police Conduct.
Bronson’s mother Sarah Piesse, 43, said: “If social services had done their job Bronson would still be alive. We have to be able to rely on social workers to keep our children safe.”
Sarah, who had last seen her boy before Christmas after a row with her ex, was not able to hold him when she went to identify him as his body was too fragile.
The mum of three, believed to have previously lost another infant son, said: “They think Kenneth died no earlier than December 29. If the social worker had pushed to get in when she got no reply on January 2 Bronson would still have been alive.”
Police said the deaths are not being treated as suspicious and the case has gone to the coroner.
Describing Bronson as a “loving, adorable little boy”, a family friend said: “He deserved so much better.”
