A 31-year-old mother involved in a vehicle fire at Camp Hill in Brisbane has died from her injuries, Queensland Police confirmed.
Hannah Baxter died at the Royal Brisbane and Women's Hospital early on Wednesday evening.
On Thursday morning #HannahBaxter was trending on Twitter, with people from around Australia paying tribute to the young mother.
Her husband Rowan Baxter died alongside their children Aaliyah, 6, Laianah, 4, and Trey, 3 on a quiet suburban street in Brisbane's east on Wednesday morning.
Police said it was too early to tell whether it was a murder-suicide or an accident, although one witness told News Corp Ms Baxter had run from the car screaming "he's poured petrol on me".
Neighbours reported hearing multiple explosions before seeing the car engulfed in flames in Raven Street at about 8.30am.
Another man who tried to help at the scene was also taken to hospital with facial burns.
Father Rowan Baxter had posted several pictures of his family on social media. Source: Facebook
The Baxters were owners of a fitness centre but had reportedly separated late last year.
The family was not involved in any Family Court or Federal Court proceedings.
Mr Baxter was a former rugby league player in the mid-2000s.
Federal member for Griffith Terri Butler and Labor's candidate for Brisbane City council Matt Campbell place flowers near the scene of the fatal car fire. Source: AAP
Detectives are still trying to establish how the fire started.
Mr Baxter's Facebook profile is littered with pictures and videos of the three children, along with comments he "loves them to the moon and back" and "daddy misses you all".
Six days ago his friend Joey Abraham wrote under a photo of Trey: "Chin up brother everything will work out just hang in there my bro alot of people care about you and the situation your facing. (sic)"
A woman looks on with her baby next to the scene of a car fire which claimed the lives of a man and his three children in Brisbane. Source: AAP
It is too early to draw any conclusions, according to Detective Inspector Mark Thompson.
"How the fire actually occurred has not been ascertained at the moment, so for us to call it a murder-suicide or a tragic accident, it's inappropriate at this stage," he said.
The three Baxter children died in the fatal car fire. Source: Facebook
"I've seen some horrific scenes - this is up there with some of the best of them."
Readers seeking support can contact Lifeline crisis support on 13 11 14, Suicide Call Back Service on 1300 659 467, 1800RESPECT on 1800 737 732 and Kids Helpline on 1800 55 1800 (for young people aged 5 to 25). More information is available at and .
