Lee Lovell on Wednesday said he was "really pleased" a four-year ordeal was finally over after the High Court reversed the reduction, reinstating nearly 18 months to the teen's minimum sentence.
His wife Emma Lovell was fatally stabbed in the heart in a front lawn scuffle after their family home north of Brisbane was broken into about 11.30pm on Boxing Day in 2022.
"I suppose I'm glad it's done. It always seemed like there was another court date or hearing," said Mr Lovell, who was also wounded in the attack.
"It will be nice to focus on the future a little bit."
The teen, who cannot be named because he was 17 at the time of the offences, was initially jailed for 14 years.
The Court of Appeal reduced his minimum sentence to 60 per cent in custody rather than the standard 70 per cent in August 2025, prompting Queensland's attorney-general to launch an appeal.
Restoring the teen's original sentence "means everything", Mr Lovell said.
"I don't believe that 14 years was ever enough to start with," he said.
"Getting at least the 70 per cent restored is a validation that Emma's life did matter."
Mr Lovell said his family was already upset by the length of the original sentence before it was appealed.
"To then have the 70 per cent reduced was just heartbreaking," he said.
Attorney-General Deb Frecklington said the state's "historic" victory marked the first successful challenge of its type to a sentence via Australia's top court in at least two decades.
"The murderer had their sentence reduced; that was a decision that I was unsatisfied with, and I'm quite sure community expectations demanded it be looked at," she said.
The killer would spend an additional one year and five months in custody after the unanimous decision, Ms Frecklington said.
"It will never bring Emma back, it will never give those two girls their mum back, it will never give Lee his wife back," she said.
"But it is a small amount of justice that we have been able to deliver."
An emotional Ms Frecklington said she could not imagine what Mr Lovell had been through.
"He's just an incredible human being and I thank him for his perseverance," she said.
"Going through the legal system is really tough."
The home invasion became the catalyst for controversial "adult crime, adult time" changes in Queensland law under the Liberal National government after it won the 2024 state election.
The legislation allows for youth offenders to face a mandatory life sentence for serious offences such as murder, with a minimum of 20 years before parole.
The High Court justices found the original sentencing judge was correct to not recognise "special circumstances" for the teen when handing him a minimum nine years and nine months.
"There was nothing about the factors of (the teen's) early pleas of guilty, his deprived upbringing, and the positive signs of his ability to rehabilitate that means that it was unreasonable or plainly unjust for the sentencing judge not to reach a conclusion of special circumstances," the High Court's decision stated.
"Indeed, as the sentencing judge observed, the early pleas of guilty by ... (the teen) ... were made against the background of an overwhelmingly strong Crown case".
The teen killer has more than six years left in detention after 500 days of pre-sentence custody as time served.