Carter Bagshaw, who is 17 months old, poured soil on the grave of his father, who was stabbed to death in July.
The campaign, which has seen stories of young people who chose positive activities instead of knife crime printed on chicken boxes, has come under fire.
Pregnant Kelly Mary Fauvrelle, 26, was stabbed to death at her home in Croydon, south London, on Saturday.
Officers were called to Welbeck Road, Barnet, on Tuesday following reports of a fight.
Four police officers were injured and three people were arrested after the violence at Westfield in Stratford, east London.