The family of the two children who died in a house fire in NSW's Hawkesbury region have released an emotional statement about their "unimaginable tragedy".

The siblings have been named as Myla Summer-Lea Hughes, 10, and three-year-old River William Higgins.

"Today, with shattered hearts, we share the devastating loss and unimaginable trauma our family has suffered following the tragedy at Bowen Mountain," parents Skye Hughes and David Higgins said in a statement.

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"Our family's world has been forever changed."

David and three other children managed to escape the blaze at the home in Bowen Mountain, about 77 kilometres north-west of Sydney, early on Monday.

"At the time of the fire, five of the children were at the Bowen Mountain home, while one child was safely with their mother, Skye, in Queensland, where the family had been preparing to reunite and begin a new chapter together in their new home."

"This heartbreaking reality makes this unimaginable loss even more devastating for all who loved them."

An online fundraiser has been set up with the parents' permission.

"These precious lives were deeply loved, and this unimaginable tragedy has left the family facing profound grief, trauma and overwhelming loss," the fundraising page says.

The parents also thanked emergency workers, doctors and nurses, family, friends and the local community for their support.

"As we mourn this heartbreaking tragedy and navigate an unimaginable loss, we respectfully ask the media and the public to honour our privacy and protect our children," they said.

"We ask for the dignity to grieve and support one another without further intrusion and will not be commenting further at this time. 

"Thank you for your understanding, compassion and respect."

An appeal is being held for funds to help cover the costs of funerals and memorials, emergency accommodation, necessities, trauma counselling and the loss of the family home. 

The fundraiser has already received more than 600 donations and raised more than $55,000. 

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The closure caused major delays, with traffic backing up towards Hillsborough.

The trio from India were known as “hardworking and grateful” and worked in NZ from 2023.

Firefighters are working to contain the oil and diesel runoff.

Commonwealth Bank has forecast the impact of potential changes to the capital gains tax (CGT) discount and negative gearing could fall flat for prospective home buyers, with only a "modest" decrease to house prices.

In a pre-federal budget analysis, economists from the big four bank, Luke Yeaman and Harry Ottley, said reforming the property tax benefits would only have a modest impact on lowering house prices and increasing productivity.

It estimates house prices could fall by 1.4 per cent with changes to the CGT discount and 2 per cent if coupled with an abolition of negative gearing.

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"The largest benefit will be higher long-term government revenue and a stronger budget," the economists wrote.

"Additional short-term volatility in the housing market is likely though, especially at a time when the interest rate cycle and slower population growth is also shifting prices and market sentiment."

Commonwealth Bank said changing the two policies may help affordability, as the median house price exceeds $1 million, but it will not solve the housing crisis.

"Boosting supply is still the key," the economists said.

The government has been dancing around what will be included in its tax reform, but has confirmed that one of the measures on the table is changes to the controversial CGT discount and negative gearing.

Critics have blamed the two property tax benefits for contributing to the housing crisis, with a Greens-led Senate inquiry finding the CGT discount is flawed and benefits investors over first-home buyers.

Two Labor senators endorsed the inquiry's report.

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However, some industry experts like the Finance Brokers Association of Australia warn that changing the policies could disincentivise investment in the housing sector and place upward pressure on rent.

If reformed, it would be the first time the CGT discount is rolled back since the Howard government raised it to 50 per cent in 1999 and the first time negative gearing is changed since it was temporarily limited by the Hawke/Keating government in 1987.

Treasurer Jim Chalmers has refused to confirm or deny whether the two policies will be changed and said the federal budget has not been finalised.

"Intergenerational fairness is a really important way that we address some of the substantial and understandable issues in our budget, in our tax system and in our economy more broadly," he said yesterday.

"What we are determined to see is a fairer economy that works for more people, including for younger people."

Chalmers told Nine's Today that there are other changes they are making to soothe housing pressures.

"If we did go down that path, I would encourage people to look right across the board at everything that we're doing in housing, not one or two policies in isolation," he said.

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Officers will monitor May weekend rides in Counties Manukau and Auckland City.

One person with critical injuries is in hospital and two others have minor injuries.

Deputy harbourmaster Peter Thomas called the near-miss dangerous and avoidable.

Alexander Gillespie warns New Zealand is not immune to rising attacks.

An Australian white supremacist who shot and killed 51 Muslims at two mosques in Christchurch, New Zealand, in 2019 has failed in an attempt to overturn his convictions.

The NZ Court of Appeal dismissed Brenton Tarrant’s claim that harsh prison conditions prompted his involuntary admission to the terrorism, murder and attempted murder charges he faced.

A panel of three judges rejected Tarrant’s bid to abandon his guilty pleas, finding it was "utterly devoid of merit".

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Tarrant, now aged 35, murdered 51 worshippers and injured dozens more in March 2019 when he drove to two Christchurch mosques and opened fire with semi-automatic weapons during Friday prayers.

Tarrant’s guilty pleas in March 2020 brought relief to bereaved families and survivors of the attack, who dreaded the prospect of a lengthy trial and feared he would use it to air his hateful views.

He was sentenced to life without parole on the murder, attempted murder and terrorism offences.

The rejection of his appeal bid – which the court noted was made 505 days after the legal deadline for it to be filed – means such a trial has once again been averted.

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His claim of mental illness was rejected

At the court's five-day hearing in February, the attacker argued his admissions of guilt were provoked by “irrationality” induced by poor mental health, which led him to desert his racist views for a time.

The judges concluded, however, that his claims of mental illness were inconsistent and weren’t supported by prison staff, mental health professionals or lawyers who had earlier represented him.

“He was not suffering from a mental impairment or any other form of mental incapacity which rendered him unable to voluntarily change his pleas to guilty,” the judges wrote in today's ruling.

“He endeavoured to mislead us about his state of mind in a weak attempt to advance an appeal in circumstances where all other evidence demonstrated that he made an informed and totally rational decision to plead guilty.”

The court's ruling also revealed that Tarrant sought to abandon his appeal shortly after making his case at the hearing in February.

The judges rejected that bid too, writing that the case was “of significant public interest and should be finally determined".

They suggested that Tarrant “began to form the opinion that the hearing was not proceeding in his favour, and as a result decided to file a notice of abandonment after the hearing concluded".

New Zealand law doesn’t require judges to allow an appellant to quit an appeal bid once it’s underway.

He will remain in jail for life

Tarrant, who has since fired the lawyers acting for him in February, remains in Auckland Prison, where he was sentenced in August 2020 to spend life in prison without the chance of parole.

The judges allowed him to abandon his appeal to that sentence, which was scheduled to be heard later in 2026.

The Australian-born man moved to New Zealand in 2017 with a plan to commit a mass shooting.

He amassed a cache of weapons and made a reconnaissance trip to the sites of his planned crimes before the attack.

The appeal court judges wrote that Tarrant had accepted the summary of facts presented to him by the police and the sentencing judge and noted that the case against him was “overwhelming.”

Evidence included footage of the attack that the shooter filmed himself and livestreamed on the internet, in which he showed his own face, and a document outlining his racist views that he published online before the attacks under his real name.

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