Having recently graduated from uni – Chris as a doctor and Peta as a lawyer – the couple wanted to see the world before settling down.
In December 1977, they left the UK for Australia, where Chris worked in a Brisbane medical centre.
Then, it was on to Mexico, followed by Belize. Chris made regular calls home to his parents and little sister Penny, 17, and Peta wrote letters to her mum.
In one dated June ’78, Peta wrote that they’d abandoned their plans to catch a bus back to Mexico after meeting an American named Dwayne.
Dwayne owned a boat called the Justin B and they were going to sail with him and his two sons, Vince, 13, and Russell, 11, to Honduras.
I don’t think there’s any more news – nothing much happens on a boat, Peta wrote, before signing off.
But when months passed with no further contact, the families grew increasingly worried.
On September 22, Chris’ dad Charles wrote to the harbour master in Belize requesting records on the Justin B. When he finally received a reply, it said Chris and Peta had been on the crew list when it left port – yet there was no record of them on board when the boat next docked.
The owner of the boat was identified as Silas Duane Boston and by this time he had returned home to Sacramento, California, with his sons.
Boston was questioned, but insisted he’d delivered Chris and Peta to Honduras.
It wasn’t until January 1979 that the family received the call they’d been dreading.Two bodies had been found floating off the coast of Guatemala six months earlier. They’d been beaten and tortured, then drowned.
Guatemalan authorities had buried them in unmarked graves. When the remains were exhumed, dental records confirmed the bodies were Chris and Peta.
Their families learned that Boston had fled to Belize to dodge a rape charge in the US. He was also suspected of being involved in the disappearance of his third wife – Vince and Russell’s mother – Mary Louise Boston.But when police went to re-interview Boston, he and his sons had disappeared.
As the years passed, Charles tried repeatedly to contact police in both Sacramento and Guatemala in an attempt to reignite the investigation.
Heartbreakingly, Charles died in 2013 without ever receiving a reply.
Then, in 2015, Chris’ sister Penny realised they were no longer reliant on letters and long distance phone calls to get answers.
‘I began to scour the internet, driven by the belief that if I looked hard enough, I would get to Boston – and the truth,’ Penny said.
Before long, Penny found Boston’s sons on Facebook.
Vince, now 50, was living in Arizona and Russell, 49, was in California. She messaged them both, begging for information on what happened 37 years earlier on that boat.
Penny then found a Facebook page for an elderly and very sick Silas Boston who was in a respite home.
‘Though I instantly hated him, my overwhelming feeling was relief he was still alive to face justice,’ Penny said.
When the UK authorities contacted the Sacramento Police with Penny’s discovery, they had information to share.
Just 11 days after Penny had messaged him, Vince had told police his father had killed his mother in 1968. He also said he’d witnessed him killing Chris and Peta. Russell backed up his brother’s version of events.
When Penny and her family met with police, the officer had their statements.
‘How much would you like to know?’ he asked. ‘Everything,’ Chris’ mum replied, without hesitation.
There, they learnt the true terror of what had unfolded.
‘Chris and Peta were on the boat when a drunken Boston started beating Russell,’ Penny said. ‘When Chris intervened, Boston tried to swing a punch at him and fell, humiliatingly, into the sea.’
According to Vince and Russell, who had grown up petrified of their father, Boston swore revenge and began plotting their murder.
They said the following night, Boston asked Chris to pull up the anchor before repeatedly bludgeoning him over the head.
Then he hog-tied Chris and Peta, beating and torturing them all night.
‘Even though Chris had a fractured skull and other broken bones, he was still trying to comfort Peta, telling her it was all going to be all right,’ Penny said.
But the next morning, Boston weighed the pair down with engine parts and dumped them overboard while still alive.
It was also revealed that over the years Vince and Russell had contacted the police, Interpol, the FBI and Scotland Yard but it was never followed up.
Boston, 75, was charged with murder in December 2016 – 38 years after the sickening crime.
In court, he pleaded not guilty. And in one last act of defiance, he exercised his right to withdraw from medical treatment.
Boston died on April 24, 2017, before he could stand trial.
‘He took the coward’s way out,’ Penny, now 57, said.
Still, the families were glad to uncover the truth.
‘My mother is 93 and now has all the answers,’ Penny added. ‘But just because you’ve found answers doesn’t mean you stop hurting.’
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