Ronnie's older brother Pinto told ITV London that the family are trying to get on with their lives with difficulty, knowing Ronnie's killer is still free.
"Ronnie was taken away from us after having been fatally shot in the stomach, from cross fire whilst attending the funeral of a childhood friend. We have been stopped from getting on with our lives as his killer still has not been brought to justice." he said.
"Whilst Ronnie is no longer with us, his killer is able to walk the streets freely. He is still able to enjoy his friends and family, whilst my little brother is dead. What's more, his killer is still able to do what he did to Ronnie and put others through what we are going through."
Azezur Khan, known as Ronnie, had just left the service of his school friend in East Dulwich and was making his way to the burial when he was gunned down at around 3pm.
The Metropolitan Police said he was hit a number of times in an exchange of gunfire between Rocknells Place and Forest Hill Road.
A fresh appeal comes just days before the second anniversary of his death on November 3.