A stepfather who was convicted of murdering a toddler almost 50 years after a Facebook photograph sparked a new inquiry has been jailed for life with a minimum term of 13 years.
David Dearlove, 71, swung 19-month-old Paul Booth by the ankles and bashed his head against a fireplace in 1968 before lying about what he had done for decades, claiming the little boy fell out of bed.
His murderous attack had been witnessed by Paul's brother, Peter, who was three years old at the time, after he crept downstairs at the family home in Haverton Hill, near Stockton, to get a drink.
Mr Booth had told police what happened after piecing together childhood memories although no action was taken.
That changed in 2015 when, incensed by seeing a black-and-white photo of Dearlove with Paul on his knee on Facebook, Mr Booth went to the police again with the allegation that his brother was murderedand an investigation was launched.
Dearlove, now a retired grandfather and married with two daughters, was arrested at his home in Great Yarmouth, Norfolk.
A jury deliberated for three days before unanimously finding him guilty of murder and child cruelty offences against Paul, Peter and their sister, Stephanie.
Teesside Crown Court heard that Dearlove was 21 when he moved in with Carol Booth, a single mother, and her three young children.
A month before Paul was killed, nursery staff were concerned about bruises on his body and the authorities investigated, with photos taken of the little boy.
Those black-and-white images of the intensely sad-looking toddler were used in court to convict Dearlove 49 years on.
At the time, the ICI worker claimed a motorbike had fallen on the youngster.
On October 1 1968, Dearlove lashed out again, causing a fatal brain injury by bashing his head.
Initially, in 2015, he told police Paul had suddenly collapsed in a chair downstairs but, at the time and during the trial, he claimed the toddler fell out of bed.
Experts told the jury a fatal fall out of bed was extremely unlikely and the extent of his injuries indicated Paul had been physically abused.
In a dramatic piece of evidence, jurors wept as Home Office pathologist Dr Mark Egan used a doll marked with the sites of Paul's bruises and bashed its head against the witness box to demonstrate how he could have been killed.
Outside court, the family said Paul would have been 50 this year but instead lay in an unmarked grave which they cannot find.
They said: "Thinking about this makes us sad, as Paul would have been a man, no doubt married and more than likely with children of his own.
"However, sadly, Paul was not given the opportunity to live his life due to the cruel and wicked actions of David Dearlove."
Outside court, Detective Inspector Mark Dimelow said the passage of time had not stopped the family getting justice.
He said: "I want to pay tribute to Paul's family and other witnesses who provided such an emotive testimony and I praise their bravery in having to relive events from 50 years ago."
Tim Roberts, defending, earlier told the judge there was no intention to kill.
He said: "We do submit that 50 years of blameless character since 1968 is a matter to which the court can, in these particular circumstances, attach considerable weight."
Paul died in hospital on the same night Peter witnessed him being attacked.
He never regained consciousness after suffering a fractured skull and died within four hours.
An inquest held in 1968 returned an open verdict and Dearlove was not prosecuted.
Ms Booth, who gave birth to Dearlove's son three months after Paul was killed, died in 1991.
They had split up in 1970 and Dearlove never saw Peter again until Mr Booth faced him in court and told the jury what he saw.