But that’s exactly what happened.
Jeremy Bamber was born Jeremy Paul Marsham, and adopted by the wealthy land-owning Bamber family.
The Bambers, who were unable to conceive children together, had already adopted a baby girl, Sheila, in 1957.
The family had a seemingly idyllic life for some years. Living at their property called White House Farm in rural Essex, Sheila and Jeremy were sent to exclusive schools and colleges, and lived a very comfortable life.
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Nevill was a magistrate and a former pilot, who financed Jeremy’s gap year to Australia and New Zealand. But it was in the latter country that Jeremy’s antisocial tendencies were exposed, when he robbed a jewellery store.
Fleeing back to London, Jeremy worked as a cook, but eventually accepted a job from his father to work on the family farm. He complained to his girlfriend Julie Mugford that he was paid minimally – but in fact had been given a residence in the city in which to live, and a car for transport.
To the local community of Tolleshunt D’Arcy, who knew the Bambers, the family was typical – which is why it was so shocked by what happened on the night of 7 August 1985.
In the early hours of that morning, police received a call from a then 24-year-old Jeremy, claiming that his father had called him and said, “Your sister’s gone crazy and she’s got a gun.” Jeremy told them that the line then went dead, after the sound of a gunshot.
At White House Farm, they discovered the bloody scene of a mass murder.
In the kitchen Nevill, 61, had been beaten and shot eight times, with four shots in the head. In her bedroom, June, 61, was found with a point-blank shot between her eyes, and several other wounds to her body. A trail of smeared blood indicated she had attempted to drag herself to safety.