The grandfather of three children who burned to death in an alleged attack as they were on their way to school says their father could not have truly loved them.
Lloyd Clarke, the father of Hannah Baxter, says he believes his estranged son-in-law is rotting in hell after his daughter also died from the incident on Wednesday evening.
Hannah and her children Aaliyah, 6, Laianah, 4 and Trey, 3 are being remembered as beautiful souls who were taken in the worst possible way.
Their father, Rowan, died on the footpath from self-inflicted wounds, police say.
"The scum rots in hell," Mr Clarke said on social media.
"If he truly loved them he would not have killed his children in such a horrible way."
Mr Clarke said the man was a "monster" who only cared about himself.
"He might have said he cared and loved his children but I know it was always about him coming first," he said.
Hannah, 31, died at the Royal Brisbane and Women's Hospital on Wednesday night after being doused in petrol by Rowan, 42.
The children - Aaliyah, 6, Laianah, 4 and Trey, 3 - died in the family car after it burst into flames on a quiet suburban street in Camp Hill in Brisbane's east on Wednesday morning.
Hannah was taking her children to school from her parents' home when Rowan jumped into the car's passenger seat, according to reports.
The car made it to nearby Raven St where, one witness said, Ms Baxter ran from the car screaming "He's poured petrol on me" as the flames took hold.
Heartbroken family members pay tribute
Hannah's brother, Nat Clarke, posted a tribute to his sister and her children on Facebook.
"RIP you beautiful souls," Mr Clarke wrote.
"I had my sister nephew and 2 nieces taken from me in the worst way possible ... I will forever love you all.
“Everyone who has been lucky enough to be a part of there lives would know just how sweet and loving these kids and my sister really were.
“The last thing my sister said to my wife was ‘I’m so excited this year will be great’.”
Mr Clarke said he is now trying to raise awareness about domestic violence against women.
Meanwhile, mourners have visited the street where the children died to lay floral tributes and pay their respects.
Friend Samantha Tone took to Facebook late on Wednesday mourning Ms Baxter’s death.
“We have had so many laughs and good times,” she said.
“Your aura would bring light and happiness to any room you were in. You will be so missed.
“I will cherish these memories dearly and I promise to love my babies as much as you did yours. I idolised you as a mother, you were a super mum.”
A Facebook fundraising page set up by Hannah's sister-in-law Stacey Roberts has so far raised more than $82,000 for funeral costs, with thousands of dollars coming in each hour.
Parents ‘exhausted themselves’ trying to help Hannah leave
Hannah's parents needed support, Ms Roberts posted, and had "exhausted themselves" trying to help Hannah, who had left her partner before Christmas.
"For all those who knew Hannah or had even just met her once would know how much of a beautiful soul she was, her children (were) her life."
The Baxters owned a fitness business called Integr8 in Capalaba in Brisbane’s east. Hannah was a trampolining champion. Rowan was a member of the New Zealand Warriors NRL squad in the mid-2000s but did not play a first-grade game.
"Australians all over the country are just shocked, saddened and devastated about what has happened," Prime Minister Scott Morrison said on Thursday.
"Hannah and her three children so senselessly and maddeningly murdered in what has occurred in a terrible act of violence and it just grieves our hearts terribly today."
Queensland University of Technology Professor Kerry Carrington, who is an expert in gender violence, believes the deaths could have been prevented with earlier intervention.
Hannah joins a worrying number of people killed by the hands of a family member, with the latest federal government report into domestic violence revealing one woman was killed every nine days by a partner between 2014 and 2016.
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