Sad Facebook posts by relatives have acknowledged that three members of the Langford family – father Anthony, mother Kristine and daughter Winona – likely died in the New Zealand volcano tragedy.
The assumed deaths would bring the death toll of Australians to 12 with another three still listed as missing.
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The aunt of Winona, 17, and her brother Jesse, 19, posted on Facebook that while "Jesse has been found alive" they "don't believe … Kristine, Anthony and Winona … have survived".
Anthony Langford's brother John and two other family members have flown to New Zealand to help search for any of the family.
Friends of the North Sydney family posted sympathetic comments to a Facebook photo the aunt put online.
The Langford relatives are among several families now in New Zealand.
But three days on from the disaster, the bodies of those presumed dead remain on White Island due to the ongoing danger of a fresh eruption.
Deputy Commissioner John Tims on Thursday said police have a plan to recover the bodies from the destination, also known as Whakaari, over a number of hours on Friday morning.
Patients arriving back in Australia
Speaking to the media in Melbourne on Thursday, the Prime Minister said 24 Australians and four permanent residents had been caught up in the volcanic eruption.
He said five Australians were evacuated to hospitals on home soil overnight and another seven would be transferred across the Tasman over the next 24 hours.
Chief Health Officer Dr Kerry Chant said 10 adult patients will be treated in NSW Health's world-leading adult burns units, with three arriving overnight at Concord Hospital and one at Royal North Shore Hospital.
The state's health department is working with Commonwealth agencies to facilitate the safe return of residents, some of whom have life threatening burn injuries.
Meanwhile, a jet from New Zealand touched down in Australia carrying more victims from the eruption to be treated by local doctors.
In an update on Thursday afternoon, NZ Director-General of Health, Dr Ashley Bloomfield, said seven patients had been flown back to Australia.
Most are going to Sydney, one to Melbourne and one possibly to Adelaide, he said.
The majority of patients left in four hospitals in New Zealand remain in a critical condition.
Three Australians still missing
Melbourne woman Krystal Browitt, 21, is officially missing, according to New Zealand police, while Martin Hollander, 48, and Barbara Hollander, 50, are still unaccounted for on the Red Cross missing persons list.
The couple's sons, Berend Hollander, 16, and Matthew Hollander, 13, were killed while visiting the site. The pair attended Knox Grammar School in Wahroonga, on Sydney's north shore, where their father had also gone to school.
"It is with the greatest sadness that I can confirm that Matthew Hollander (Year 8) and Berend (known as 'Ben') Hollander (Year 10) have passed away in hospital as a result of injuries sustained in the White Island volcano eruption," the school's headmaster Scott James wrote in a letter to parents. "Please take some time to reflect on the lives of Matthew and Ben and this devastating loss for our community.
The Hollander family released a statement saying they were "absolutely heartbroken".
"We are absolutely heartbroken by this loss. Ben and Matthew were wonderfully kind and spirited boys who lived short but very fulsome lives. They loved Knox and all their friends, and the Australian sports and outdoor lifestyle they adopted on moving from the United States six years ago. They had a positive and lasting impact on everyone's paths they crossed. The family requests privacy at this difficult time."
Ms Hollander grew up in Chicago and moved to Sydney about five years ago with her husband and sons, according to the Chicago Tribune.
Melbourne woman Krystal Browitt, 21, is officially missing following the eruption. New Zealand police say she is neither in hospital nor has been discharged.
According to the Herald Sun, her father Paul is in a coma in an Auckland hospital, while her sister Stephanie is in a Christchurch burns unit.
Her mother Marie, however, is unharmed after choosing not to go on the White Island tour.
"I can't imagine what Marie is going through all alone," the family's neighbour, Supreetha Konda, told Channel 7.
A friend described Krystal, who was celebrating her birthday on the cruise, as "an amazing person" who "always had a smile on her face".
Death toll rises
Jason Griffiths, 33, and couple Karla Mathews, 32, and Richard Elzer, 32, all from Coffs Harbour, were confirmed dead in a joint statement issued by their friends and the Department of Foreign Affairs and Trade (DFAT) last night.
The trio had been holidaying with a group of friends on the Royal Carribean Ovation of the Seas cruise ship when the volcano erupted.
"On the 4th of December 2019, we embarked upon a cruise as a group of nine close friends who were looking forward to a wonderful holiday together," the statement said.
"We enjoyed the first five days of our trip and have many memories that will stay with us forever.
"On the 9th of December 2019, we were devastated by the news that three of our friends were visiting White Island on a shore excursion during the time of the eruption.
"Some time later, we discovered that two of our friends, Richard Elzer and Karla Mathews, were still on the island. We have been advised that there are no signs of life on the island.
"We then located our third friend, Jason Griffiths, in a hospital in the early hours of the next morning.
"From that moment until the moment of his passing, Jason was surrounded by friends and family members.
"We are incredibly saddened to have lost three of our closest friends."
Mr Griffiths had reportedly suffered burns to 80 per cent of his body.
Four other Australians were confirmed dead by their families on Wednesday, including 53-year-old Adelaide lawyer, Gavin Dallow, and his 15-year-old stepdaughter, Zoe Hosking, 47-year-old Brisbane mother, Julie Richards, and her 20-year-old daughter, Jessica.
"Matthew was a vibrant member of the Class of 2023. He was involved in Cadets and representing the School in Basketball, Squash and Debating. He was elected as a Mentor Representative in 2018/19. Matthew had a close circle of friends and was popular among his peers. He was always enthusiastic about life and was actively involved in school and year group activities.
"Ben was actively engaged in sports and co-curricular activities at Knox, developing a passion for AFL, Cadets, CRU and his biggest passion, Baseball. He had a great love for the outdoors and camp. Ben was a compassionate and enthusiastic student, with an interest in software design. Ben's engaging smile and quirky sense of humour made him a good mate to his close group of friends and a welcome member to every classroom."