The mother of the Marine A has said that she hopes to have him home for Mother's Day but warned that if he had more support from the military this might never had happened.
Frances Blackman, 77, says that following the appeal court's decision to quash Sergeant Alexander Blackman's murder conviction and replace it with that for manslaughter she found herself crying tears of joy rather than despair for the first time in years.
She now hopes that after Friday's sentencing hearing he will be released almost immediately on the basis that he has already served more than three years behind bars, saying that to have him home for Mothering Sunday "would be the best present ever."
Despite her relief, Mrs Blackman used a rare interview to criticise the military for failing in their duty of care toward her son.
Blackman's original court martial heard no evidence as to his mental state when he shot an injured Taliban insurgent at the end of a "hellish" six month tour of Afghanistan and the option of convicting him of manslaughter was not offered to the panel.
The murder conviction was last week overturned by the panel of judges who replaced it with a verdict of "manslaughter by reason of diminished responsibility" on the ground he was suffering from an "adjustment disorder" as a result of his combat stress.
"I was shocked that he did what he did. But I firmly believe he felt he was looking after his troops," Mrs Blackman said.
"He promised the mums of the other Marines that he would look after their sons. I think that's what he was doing, looking after his troops.
"If he had a padre or someone else of senior rank with him to talk to I'm sure this wouldn't have happened. It's life and death.
"Every time they went out on patrol they didn't know if they were going to be blown to pieces. Every step could have been their last step.
"You are living on your nerves. Alexander would have put himself in danger rather than anyone else."
She told how her daughter phoned her last week to tell her that five of the country's leading judges had overturned the court martial conviction.
Mrs Blackman, a volunteer at her local food bank, said: "I was crying. Tears were streaming down my face. "I've shed quite a few tears the past few years but these were tears of joy. I'm just so happy."
But one of the real heroes is his wife, who has supported him every step of the way, she said.
"Claire deserves a medal," she continued. "It can be hard for a mum to give up their boys to another woman but when you see what she has done for him you can't have any doubt how much she loves him."
Mrs Blackman learnt on her 74th birthday that her birthday that he would serve a minimum of ten years behind bars and has prayed for him every night since.
Her husband Brian had died in January 2011, just months before Blackman was sent on the fateful tour and it was against this background of grief that he arrived in Helmand.
"It would have broken Brian's heart to know what happened," Mrs Blackman said. "Alexander really struggled with his dad's death. He was stuck in the traffic after there was an accident near the Palace Pier and he couldn't get to the hospital in time to see him. It always ate him up, that."
Even after everything that the family have been through, Mrs Blackman is still proud of his time in the Royal Marines.
"He might be 6ft 3in but he is still my little boy," she said, clutching a photograph of him. "Alexander would always give me a cuddle. He was always affectionate. When he got his first job he said he was going to pay for everything from then on.
"He was a lovely boy. When he joined the Marines at the age of 23 I was worried of course but I supported him.
"His dad had been signed up before as a tank driver and he was so proud. Brian was so proud when Alexander went up in rank."
Blackman will be sentenced at the Royal Courts of Justice on Friday. If the sentence is six years or less he will be released on the basis that he has already his time in prison.