Trevor Brecknell got to see his new daughter before he died. It is one of the few things his killers could not take from him.
After visiting his wife and two-day-old baby in hospital, he drove to Donnelly's bar in Silverbridge.
It was the evening of December 19 1975. Nearly Christmas. Trevor, 32 and now a father-of-three, was surrounded by friends and relatives, and a sing-song was under way.
Within minutes he was among three dead. Six people were injured, including Trevor's brother-in-law who was shot five times, and his sister-in-law, who survived being shot in the head.
The loyalist gang killed 24-year-old Patsy Donnelly first shooting him as he pulled up to the petrol pumps.
One survivor recalls what happened next.
"I heard a banging outside then the door was kicked in. Shots were fired into the bar.
"Trevor and I were sitting opposite the door. It had a heavy spring on it and it slammed back in the gunman's face. He broke the glass panel with his gun and began firing through the broken glass.
"Trevor just slumped forward beside me without saying a word. I got shot twice and fell to the floor. Everyone else was huddled in the corner, with the man still shooting."
Michael Donnelly (14), the bar owner's son, died when the gang threw in the bomb shouting: "Happy Christmas you fenian bastards."
Another witness later said he recalled "hearing a blurred figure laughing" as he fell to the ground.
In recent years Trevor Brecknell's eldest son, Alan, has pieced together what happened that night and has learned that security force members were among the gang.
"There was always an allegation of security force involvement," he says.
"I grew up believing it was as little as making sure that the roads were kept clear. In more recent years it has been confirmed to us by the police that there was a member of the UDR, a reserve RUC officer and loyalists from Portadown involved in the attack. The UDR member was subsequently killed by the IRA in 1976 and it's been alleged he was involved in a number of other incidents including the Dublin and Monaghan bombings. His name was Robert McConnell."
It was not until the more positive atmosphere that followed the ceasefires of the mid-1990s that the families bereaved at Donnelly's bar felt it was safe to begin to dig deeper into the events.
During a business trip to Derry, Alan knocked on the door of the Pat Finucane centre the human rights group named after the solicitor killed in a conspiracy between the state and loyalist paramilitaries, the full truth of which is still emerging.
They helped gather statements from those connected to the tragedy at Donnellys and issued an appeal for the RUC officer who led the original investigation to come forward. He agreed to meet them.
"His opening comments to us were, 'I have no doubt that there was collusion between members of the UDR, RUC and loyalist paramilitaries on the attack on Donnelly's bar'.
"While we maybe knew it in the back of our own heads, it was still shocking to hear from an official source," Alan says.
The relatives did not have the names of those believed to have been responsible but they lobbied the authorities and took court action to force more information into the open.
Alan eventually became a researcher for the Pat Finucane Centre, forging close ties with Justice for the Forgotten, representing those bereaved in the 1974 Dublin and Monaghan bombings in which 33 died.
The two groups sent a team to scour the mass of paperwork in the public records office in London each time new government files were released under the 30-year rule.
UDR members have been linked to the Dublin-Monaghan bombings and the Donnelly's bar attack, so when one of the team discovered a document entitled 'Subversion in the UDR', they all took notice.
"This is the most significant thing we have found at any stage.
"It was quite alarming to find that the British government at the highest level knew, as they put it themselves, that there was 'subversion within the UDR'," Alan says.
"They knew that it went as far as getting guns for loyalists and involvement in murder."
Alan now knows that more than two years before his father's death British authorities were aware that large numbers of UDR members were connected to loyalist paramilitary groups, and were the "only source of modern weapons" for loyalists. The government, nevertheless, expanded the regiment's role.
He is shocked, but says it is also a positive step on his journey.
"It is official; it settles that part of the story now. No-one can say it's the rantings of Alan Brecknell or whoever. It's official."
The files he helped discover have now been passed to the police Historic Enquiries Team to help shed light on other cases.
Trevor Brecknell was from Birmingham but none of his English relatives attended his funeral.
His parents were told Trevor was killed by the IRA and it would not be safe for them to cross the Irish Sea. The RUC is blamed for the false information.
"That to me is unforgivable," said Alan suddenly struggling to hold back tears. "Granny Brecknell died not knowing what really happened to her son."