A depressed mother treated her son to a McDonald's Happy Meal before filling his rucksack with rocks and tying their hands together before jumping into a reservoir and killing them both.
Emma Sillett, 41, had taken five-year-old Jenson Spellman for some food before driving them to the deserted spot in Derbyshire to end their lives.
The social worker left an emotional note in her car which explained she was tethering herself to her son because she could not bear the thought on him 'drifting away'.
Chesterfield Coroner's Court heard that little Jenson was found facing Ms Sillett and had been 'tied to her by his wrist'.
Detective Constable Rebecca Fearon told the inquest: 'She had a rucksack on her back which contained rocks.'
During the hearing, the court also heard that Ms Sillett had struggled for years with depression and had previously suffered three miscarriages.
Despite this, police said the breakdown of her relationship with Jenson's father had appeared to have been the 'the major issue in her life' that had triggered the tragedy.
Her suicide note made it clear she wanted to end her life, but could not stand the thought of leaving her son to face life without her.
Their bodies were found at Valehouse Reservoir in the Derbyshire Peak District, two days after they were reported missing on November 20 last year.
In her note the mother said she would leave 'a marker' to help locate their bodies.
It also described how she had tried to carry out her plan the day before but she had stopped because Jenson had 'got frightened'.
Mother treated son to McDonald's before jumping to death
Emma Sillett, 41, had taken five-year-old Jenson Spellman for some food before driving them to the deserted spot in Derbyshire to end their lives.
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