A Brisbane woman has been charged with murder over the death of her disabled half-brother, who weighed just 29 kilograms.

Emergency teams found 56-year-old Isaac “Ike” Oar dead at a home in Ayr on the night of August 10, 2023.

Police said in 2025 investigations had shown he had been “experiencing serious malnourishment”.

Oar had Down syndrome and was non-verbal. Police said investigations into his prior treatment were complex.

Officers confirmed on Wednesday – almost three years after Oar’s death – they had charged 70-year-old Maria Arrieta with domestic violence murder.

Arrieta is the half-sister of Oar, and worked as a disability support worker.

She is from Forest Lake in Brisbane, more than 1000 kilometres south of the north Queensland town where Oar was found.

Arrieta was due to appear at Brisbane Magistrates Court on Wednesday.