First picture of youngest victim of Britain's knife scourge - the boy, 14, who wanted to change the world

David Idowu, 14, looks heartbreaking innocent as he sits on a sofa with his mother, Grace, and leans lovingly into her embrace.

The schoolboy died on Monday from injuries inflicted in a row three weeks earlier, making him the 19th teenager to be stabbed to death in London this year.

Innocent: David Idowu, 14, with his mother Grace. He died on Monday after being stabbed in a row three weeks ago

His mother, 48, and father Tim, 56, today paid an emotional visit to the spot in Southwark, south London, where he was stabbed just yards from their home.

In the driving rain, Mrs Idowu fell to her knees and wept uncontrollably as other family members clutched each other for support.

Holding a gold balloon with 'God Bless David' written on it, she sang a hymn in her son's memory, crying until her family helped her to her feet.

She said: 'We love you David but God loves you more. May your heart and soul rest in peace.'

Accompanied by David's brothers, Peter, 18, and James, 13, the couple revealed their  son had dreamt of becoming a politician and changing the world when he grew up.

Mr Idowu said: 'David always thought of what to do now and what will happen in the future. He believed change can only come through good world leaders.

'He was the light of this house, organised and managed things. Our lives can never be the same again.'

Tears: David's mother sinks to the ground and weeps as she visits the spot where he was stabbed

He described his son as the 'light of this house' and said he had recently been to Madame Tussauds to have his picture taken with their figure of Bill Clinton because he admired him and wanted to emulate him.

His wife added: 'David is with his heavenly father but we shall see him again. The body of Christ let us call for revival on this great nation and God will hear us.'

David was stabbed in the chest and stomach three weeks ago after being confronted by a gang of youths.

Police believe he may have been singled out because of his school uniform, the blue and grey of Walworth Academy.

Two days after the attack on June 17, he had been due to give a speech urging others to give up knives at the world's biggest speaking event for young people.

Instead, the academic schoolboy was fighting for his life in hospital when the speeches were made and a friend had to take his place.

Church elder Odunayo Otti, who is a member of the Christ Apostolic Church in Bermondsey where the family worship, said today: 'He was a sweet and loving boy, never mixed up in any trouble.

'He was always at church with his family and worked hard at school. We're all just trying to help the family cope as best they can.'

Police have not yet revealed whether a 16-year-old remanded in custody last month accused of attempting to kill David will be charged with murder.