A FIVE-year-old boy who died while in foster care may have had heroin in his system, according to a toxicology report described by a child protection worker.
The small boy who lived with epilepsy and hepatitis C was put into foster care shortly after his birth because his biological mother was a drug addict.
He died on the couch of his foster family in 2015.
The Daily Telegraph reports the boy had an unknown bruise on his skin "possibly from a syringe", had been ravaged by insect bites and had a bad burn on his back.
It reports teachers at the NSW boy's kindergarten had called an ambulance because the burn appeared so severe.
The school also raised concerns with Family and Community Services, the Telegraph reports.
The dead boy's older sibling was being looked after by the same family, but has not returned to their care since the death.
The case was being managed by Uniting Care, which is already under scrutiny following the death of a 15-year-old teen who died after injecting methamphetamine and heroin.
The Telegraph quotes a Uniting Care "insider" who said the five-year-old boy's toxicology report showed his bloody contained "diazepam, morphine, opiates and possibly heroin".
Revelations about the boy's death comes as Queenslanders remain stricken after the death of young teenager Tiahleigh Palmer, who was allegedly killed by her foster father Rick Thorburn in October last year.
Mr Thorburn has been charged with her murder.
Tiahleigh's foster brother Trent Thorburn stands accused of having sex with the 12-year-old, and has been charged with incest.
The allegations prompted Queensland Premier Annastacia Palaszczuk to announce a review into the state's foster system.
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