Aishwarya Aswath could still be alive if not for stretched Perth hospital staff failing to realise the seven-year-old was experiencing sepsis, a coroner has found.
Aishwarya died on Easter Saturday 2021, hours after presenting to the Perth Children's Hospital emergency department with a fever and unusually cold hands.
She had been left in a waiting room for more than 90 minutes, despite her parents pleading with staff - who they described as rude and dismissive - to escalate care as her condition deteriorated.
An inquest into her death was told there was intense demand on staff who missed repeated opportunities to identify the seriousness of her condition.
Premier Mark McGowan has insisted the hospital was not understaffed that night because it had its full rostered complement.
But in her long-awaited written findings on Friday, Deputy State Coroner Sarah Linton said while that was "technically" correct, it was clear the roster had been inadequate to deal with demand.
"Aishwarya's parents brought their daughter in to hospital because they knew she needed help," Ms Linton said.
"But due to the pressures on them, the medical and nursing staff missed the signs that she was critically ill from sepsis and failed to rescue her.
"It really is as simple, and as tragic, as that."
With proper treatment, there was a "small possibility" Aishwarya's life might have been saved.
"That chance, albeit statistically small, was enormously significant to Aishwarya's family," Ms Linton said.
The coroner did not make any individual adverse comment against the staff members involved in Aishwarya's treatment.
But she noted there were multiple opportunities where clinicians could have escalated her care, had they stopped to consider her symptoms more closely and listen to her parents' repeated concerns.
The "most significant" arose when junior waiting room nurse Tahnee Vining observed Aishwarya to be grunting in pain with an elevated heart rate, respiratory rate and temperature.
Ms Vining did not consider sepsis, despite Aishwarya meeting the documented threshold for further investigation.
The nurse was unable to monitor Aishwarya because she was repeatedly called away on other duties, including assisting a patient resuscitation.
Another nurse had raised concerns in an email to their union in March 2021 about the hospital's staffing levels, and Ms Linton said it appeared then-health minister Roger Cook had also been generally informed of the situation.
"It is deeply concerning to then see these events play out only a few days later, exactly as the nurse had feared," the coroner said.
"The background points to systemic issues surrounding the resourcing of the ED, rather than the behaviour of individuals in this case."
While the state government had implemented various changes to improve Perth Children's Hospital, it was too late for Aishwarya and her family.
"It shouldn't take the death of a beloved little girl for ... the government to stop and consider what more it can do, and how much more money it should spend, to keep children safe when they visit our specialist children's hospital," Ms Linton said.
"There is no point in having a state of the art facility, if the staff working within it are stretched beyond capacity and parents lose their trust and faith in them."
The coroner has formally backed several recommendations put forward by the Australian Nurses Federation.
They include the priority implementation of nurse-to-patient ratios, better monitoring of sepsis symptoms, improved access to digital record-keeping tools and a standalone resuscitation team for Perth Children's Hospital.
Health Minister Amber-Jade Sanderson said the government was implementing the recommendations and would not wait for an industrial agreement with nurses before introducing nurse-to-patient ratios.
She said staff numbers in the emergency department had increased significantly.
Liberal leader Libby Mettam said the report highlighted the McGowan government's failure to properly resource the hospital.
"The government has nowhere to hide," she said.
The coroner paid tribute to the "grace and dignity" of Aishwarya's father Aswath Chavittupara and mother Prasitha Sasidharan, adding that she understood why they would "never forgive" the health system.
Through their lawyer, the couple said it was "incredibly upsetting" to know Aishwarya had been deprived of a chance at survival.