A British mother says she sees her nine-year-old son's "frightened face" every day after watching an electric gate crush his head outside her parents' retirement home.
Samantha Whittle said her son Jason Keet leaned through a gap in the gate to press the button to open them on April 13, 2006, the Daily Mail newspaper reports.
As he pressed the button, the gate swung open but his head and upper torso became stuck.
His skull was crushed by one tonne of pressure, triggering a fatal heart attack.
Mrs Whittle revealed the harrowing details in a victim impact statement read to Bournemouth Crown Court after the owners of the fence, Faulkner Gates Limited, were fined $136,000 for safety breaches.
"When you watch the child that you have loved, cared for, cuddled and nurtured for nine-and-a-half years dying in front of you, then part of you dies too," she said.
"I have an ache in my heart that never goes away ... I was left there feeling helpless, trying and trying to save Jason, trying to make everything right.
"When I close my eyes, I still see every detail and feel every agonising second of that day."
Jason's 12-year-old sister Rihanna also witnessed the accident.
Mrs Whittle's parents, Stephen and Marion Culling, moved out of their home because they were too traumatised.
"My wife and I sank lower and lower into despair until one day I woke up and decided we must begin to live again," Dr Culling said.
The company that built and installed the gates admitted the gap between the brick post and the fence was too wide under its own guidelines.
The firm said it was sincerely sorry for the incident.