Archie Battersbee received a voice note days before he was found unconscious which told him his mother had wanted to have an abortion, an inquest heard.
Archie, 12, died in August when his life support was withdrawn following his parents' legal battle with the NHS hospital treating him in London.
He was found at the family home in Southend, Essex, on 7 April last year.
Family members told the inquest they did not believe he was trying to harm himself.
No images or videos of Archie taking part in online challenges were found on his phone, a detective told the inquest.
Det Sgt Tiffany Gore told the inquest officers found a voice note from 3 April in which a young male voice, said: "Oi Archie, do you know why you're angry?
"Because your mum wanted you to be an abortion."
She said that a second audio note on the same date said: "You and your mum are the ones sat there all night using."
The inquest in Chelmsford continues.
Image source, Hollie Dance
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