Apprentice contender Raleigh Addington has revealed that he quit the show to dash to his brother's side after he was badly wounded serving in Afghanistan.
Viewers will not see him leave in Tuesday night's episode but the 23-year-old said there was "never any question" of staying on the show after hearing the news.
His brother, Captain Ed Addington, was injured in an explosion just before the candidates were due to be briefed on their second task on the hit BBC One reality show.
Raleigh said: "At the start of the second task, I was contacted by the producer of the programme who told me that my mother was on the emergency number and I immediately feared the worst. My mind was buzzing with all kinds of emotions, had Ed been killed or injured in Afghanistan."
His brother was flown to Selly Oak hospital in Birmingham suffering from a collapsed lung, a brain haemorrhage and multiple fractures to his arms and legs.
Raleigh said: "He was lucky to be alive. There was never any question of me staying in the show and I knew that I had to be with my parents and my two other brothers to support Ed. I walked out in a daze, not really being able to comprehend the gravity of the events. Lord Sugar gave me a call after I left to make sure my brother and family were okay - it was great to hear from him."
Ed said when he woke up and saw his brother he thought he had been fired after the first task.
He said: "He knows family comes first, but I truly believe Lord Sugar lost his best Apprentice that day."
Ten days after Ed was flown back to the UK, Raleigh took a job at Tickets For Troops, a charity which works with organisations in the UK to supply tickets to events for British troops and their families.
Lord Sugar said: "Raleigh's decision to step down from the show proves that family should always come before business. We were in full support of his choice and I think his charitable work is particularly admirable. I wish him all the luck for the future."