Police are investigating the seven-month-old’s death after he was taken to Muswellbrook Hospital in an unresponsive state just after 3pm yesterday.
Despite the efforts of hospital staff, the baby was unable to be revived.
Officers from Hunter Valley Police District were notified and started an investigation.
A crime scene was established at a home in the Hunter Region and examined by specialist forensic officers.
A post-mortem examination will be conducted to establish the cause of death, but police said it was being treated as suspicious.