Child protection workers were deeply concerned gaps were opening in a community beset by drug use and domestic violence before a boy died at Wyong.

A retired judge will investigate if more could have been done to protect the boy as police conduct forensic tests for signs of cannibalism.

A 32-year-old woman, who can't be identified for legal reasons, approached police in Wyong and allegedly told them she had consumed parts of her four-year-old son.

Child protection workers were deeply concerned gaps were opening in a community beset by drug use and domestic violence before a boy died at Wyong.

The Central Coast tragedy refocuses attention on NSW’s parlous child protection system.