The mother of murdered teenager Jay Whiston will be handing out leaflets in Colchester today appealing for information to help find the killer of James Attfield.
James was stabbed 102 times in Colchester's Lower Castle Park.
A 38-year-old man arrested at the beginning of the investigation has been released without charge. A 27-year-old woman is on bail until tomorrow morning.
Jay's mother Caroline Shearer set up the charity Only Cowards Carry to help get knives off the streets.
His killer, Edward Redman, was convicted Jay's murder by a jury at Chelmsford Crown Court last week.