The brutal nature of the murders committed by David McGreavy disgusted the nation.
Even after 40 years, his crimes are still some of the most horrific of modern day murders.
McGreavy killed three children in Gillam Street, Rainbow Hill, Worcester, then impaled their corpses on railings.
The children - Paul Ralph, four, and his sisters Dawn, two, and nine-month-old Samantha were all killed using different methods.
Paul had been strangled, Dawn was found with her throat slashed, and Samantha died from a compound fracture to the skull.
They were the children of Dorothy Urry, who now resides in Andover, Hampshire.
McGreavy, who was the lodger living with the children's parents, was babysitting in April 1973 when he committed the murders. He was later dubbed the Monster of Worcester.
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