Keith Lyon was stabbed to death on downland at Woodingdean in Brighton 34 years ago in a crime which shocked the nation.
His mother, Valda, who is now 82, made an emotional plea in The Argus last week for help in solving the mystery.
Since then, police have received a number of helpful calls even though the murder happened such a long time ago.
What they are missing is the one call that may reveal really vital information about the savage killing.
Someone must know what happened to this defenceless 12-year-old boy in a lonely place ironically known as Happy Valley.
It's likely more than one person was involved and that the killing could even have been the work of a gang.
All it needs is for someone to come forward with the piece of vital information. This, allied to modern, scientific detective methods, could help secure a conviction even at this late stage.
Mrs Lyon is now an elderly woman and this killing ruined much of her life. Someone with a conscience must come forward and give the police information that would give her peace of mind.
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