A carer for disabled Adelaide woman Ann Marie Smith has spent a night in custody and is set to face court charged with manslaughter over the 54-year-old's death.
The 68-year-old woman was detained on Thursday, with detectives at the same time conducting a search on her home.
Police allege Ms Smith, who suffered from cerebral palsy, died of serious criminal neglect and her death was preventable.
She passed away in hospital in April from septic shock, multiple organ failure, severe pressure sores and malnourishment while under the care of the National Disability Insurance Scheme.
Detective Superintendent Des Bray said police would also continue to develop a comprehensive brief ahead of a coronial inquiry and were still investigating the dead woman's financial affairs.
The charged woman is expected to appear in Adelaide Magistrates Court on Friday.