The mother of a Bradford soldier killed alongside five colleagues in a bomb blast has spoken of the heartbreaking ‘quirk of fate’ which led to his death.

Private Christopher Kershaw, of Idle, had offered to stand in as the driver of a Warrior armoured vehicle which was blown up just minutes later during a patrol in Afghanistan.

The 19-year-old, a former pupil of Hanson School, died alongside Sergeant Nigel Coupe, 33, Corporal Jake Hartley, 20, and Privates Anthony Frampton, 20, Daniel Wade, 20, and Daniel Wilford, 21 when an improvised explosive device (IED) detonated under their Warrior in Helmand Province on March 6 2012.

Speaking after an inquest into the six soldiers’ deaths, Pte Kershaw’s mother, Monica Kershaw, spoke of how difficult it had been for her to hear that her son was not originally intended to be in the patrol. But she said she was proud he had been so ready to “do his duty”.

She said: “This process has been one which a mother never wishes to have to undertake. I feel like I have been involved in a nightmare, from which I can never awake, leaving me emotionally drained.

“From the information we have heard at the inquest, it was a pure quirk of fate that Chris should have been kitted up and got into a patrol for which he was not intended. I am still struggling with this – but how like him to be ready to do his duty for his fellow soldiers. How proud I am of his call to duty.”

Pte Kershaw’s father, Brian, who attended the inquest, paid tribute to his son, saying: “Chris always knew what he wanted to do and followed his heart, he did what his grandfather did and became a soldier.”

Asked about his son’s decision to take the place of another soldier on the patrol, who was returning from a shower, he said: “Chris knew what he was there to do and so would any of the other lads in the situation.”

The teenager’s stepmother, Sharon, said: “We are incredibly proud of what Christopher and the other lads were doing and we send our best wishes to the other lads who are still out there doing such a difficult job. He was Brian’s baby and he always will be. He was besotted with him. What happened was horrendous and nothing can change that, but the questions that we had have been answered in full. It’s more clear what happened and it’s easier in our minds.”

Significant steps have been taken to improve the army’s Warrior vehicles in the wake of the deaths of six soldiers in Afghanistan, the coroner said yesterday, as he ruled they were unlawfully killed. The vehicle was patrolling with another Warrior when it was blown up about 25 miles north of the capital of Helmand, Lashkar Gah, bringing the biggest single loss of life for British forces in Afghanistan since an RAF Nimrod crash killed 14 people in September 2006. Sgt Coupe, a member of 1st Battalion The Duke of Lancaster's Regiment, and his comrades, all members of the Yorkshire Regiment's 3rd Battalion, died of blast injuries caused by the explosion. The inquest at Oxford Coroner’s Court has heard that no other vehicle of its type was designed to withstand a blast of its type, but that since the tragedy, improvements have been made to Warriors.

Giving a narrative verdict, Oxfordshire coroner Darren Salter said: “At least it is very clear from the evidence of the two pathologists and the evidence of those who witnessed the strike that they did not suffer.”

The court was told that eight new fuel tanks have been fitted so far to the vehicles that are being used in Afghanistan, with 21 more due to have the upgrade, and the coroner said that “significant steps” had been completed in making improvements to the vehicles and there was no need for a formal report under his powers because he was satisfied the areas of concern had been addressed.

Afterwards, Mr Kershaw said: “We hope there is a lesson to be learned from this inquest that will help and protect all soldiers in the future.”