Police and paramedics were called to the property at 6.40am on Monday after an occupant found the child unresponsive. CPR was administered but the boy died at the scene. He was one of multiple children living at the home.
Detectives have interviewed the boy's father and stepmother, who were home at the time. The carers told detectives duct tape was used to help the children sleep. Police sources confirmed the children were restrained in sleeping bags with duct tape, which was also used as a blindfold at bedtime.
Detectives believe the boy lived with intellectual impairment. Police were called to the home last year following a concern for welfare, which triggered a referral to DCJ. It is unclear whether the family was subject to regular monitoring by the agency, which has been contacted for comment.
A post-mortem examination will determine the cause of death. The surviving children have been moved to live with relatives. No arrests or charges have been laid. Specialist officers, including from State Crime Command's Homicide Squad, are investigating.
Anyone with information is urged to contact Crime Stoppers on 1800 333 000.