Ryan Manser was killed in 2007
An Exeter woman who smothered her son and later hanged herself in a Sussex psychiatric unit thought she was the messiah, an inquest has heard.
In April 2007 Emma Manser, 24, killed four-year-old Ryan and repeatedly stabbed her mother, Wendy Richards.
Ms Richards told the inquest her daughter thought she was the messiah and had a history of mental illness.
She added that her daughter had repeatedly been admitted to hospital and had been released too soon.
The inquest at Honiton was also told that Ms Manser had unsupervised access to Ryan and that this would form a key issue at the hearing.
Describing the night Ryan died Ms Richards told the inquest her daughter was "demented" and that she just wanted to hurt people.
Following the attacks Ms Manser was arrested and charged with murdering Ryan and attempting to murder her mother.
She was taken to The Dene mental health unit, in West Sussex, for psychiatric assessment where she killed herself in July 2008.
The inquest was told that she left a note which read: "I'm sorry, I cannot live with myself knowing I killed the only good thing in my life".
The inquest continues.