Billy Cox was shot on Valentine's Day
The father of a 15-year-old boy gunned down on Valentine's Day in 2007 has said he still "speaks" to his dead son.
Billy Cox was shot on the doorstep of his home in Clapham, south London, and was found by his 12-year-old sister.
The family moved to Camberwell after the murder but his father Tommy, 55, said he visits the home in Fenwick Estate "to be on my own with Billy".
Appealing before the third anniversary, officers from Trident said people should come forward and name a suspect.
Police believe Billy might have known his attacker.
Since 2007 a 20-year-old man has been arrested twice over the murder but was released without charge.
Tommy Cox, a builder, said: "I like to come here early, you know, 4am, 5am, to be on my own with Billy and say to him, you know, see you soon.
Appealing at the scene he added: "It is an opportunity to tug on some heartstrings, if there are any hearts out there.
"This guy is not Al Capone out there he is just a little thief boy, there is nothing to be frightened of.
"If someone wants to do a decent thing for Valentine's Day, make a phone call."
He said his daughter Elizabeth, now 15, is still trying to cope with the murder.
"Elizabeth still cannot talk to me about the day she came home. She is getting counselling at school and they say she is getting on a lot."
In 2008 a £20,000 reward was offered for information on the killer.
Det Insp Russell Duke said: "We understand it could be life changing for them because the fallout from it in some circles is immense
"We will treat all calls in the utmost confidence and urge you to pick up the phone, for the sake of Billy's family."