Four-year-old Willow Dunn had pressure sores to the bone when she was found dead in a Brisbane home last year.
The evidence was heard during a committal hearing for the girl's father, Mark James Dunn, and stepmother Shannon Leigh White who are charged with her murder.
Willow, who had Down syndrome, was found dead on May 25, but is believed to have died about two days before.
She was found in "extremely confronting" conditions in her Cannon Hill home, police said at the time.
Police responding to the property were told of the sudden death of a four-year-old girl, with information coming from paramedics, Senior Constable Andrew Kitas told Brisbane Magistrates Court on Tuesday.
He said details given to officers included that it appeared her face had been eaten by rats.
Willow had very deep pressure sores "to the bone" that may have developed over weeks, forensic pathologist Dr Andrew Kedziora told the hearing.
The majority were on her back and likely due to immobility.
"If a child is able to move even a little bit and change the position this will immediately improve the circulation or blood flow through this area and slow down or reverse those changes," Dr Kedziora said.
"So the fact that these pressure sores are present and they are so deep shows that for quite a while the child did not move at all."
Sores on her pelvic bones may have been caused by pressure from clothing like nappies.
Dr Kedziora also found evidence of pancreatitis, most likely caused by chronic dehydration, and nutritional deficiencies.
The last contact Willow had with a doctor was in 2018 when she was "quite lively and behaving normally".
At the time her height was on the 25th percentile, but by the time she died it was at the fifth percentile, Dr Kedziora said.
If the child stopped growing suddenly that drop would take eight months.
"But this period may be shorter if some of the stunting was caused by intermittent disease (or) childhood infections," he added.
Magistrate Mark Nolan committed Dunn and White to stand trial in the Supreme Court at a date yet to be decided.
They each face one count of murder and one of child cruelty.
White and Dunn remain in custody.
Australian Associated Press