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Liam Gardner made device from dressing gown cords to hold up computer. Device reminiscent of cartoonist Heath Robinson's mad machine drawings. After only a few days Liam became fatally tangled while using it as a swing. His family in Ebbw Vale, South Wales, rushed to help but couldn't save him. Inquest in Newport, South Wales, returned a verdict of accidental death.

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assistant: By. Kieran Corcoran. A nine-year-old boy accidentally hanged himself on a rope 'Heath Robinson-type' contraption by his bunk bed made of dressing-gown cords he used to watch films with his brother. Liam Gardner, from Ebbw Vale, South Wales, set up a network of cords by the bed to hold up his tablet computer while it played videos, an inquest heard. But the boy, who shared the room with his brother, got caught up in the cords while using them as a swing and was strangled. Hanged: Liam Gardner, nine, (pictured left and right with his father Shane) became caught up in a rope contraption he set up in his room while using it as a swing. Coroner David Bowen compared the set-up to the creations of W Heath Robinson, an early 20th century cartoonist famous for drawing ostentatiously complicated machines. The inquest heard how Liam's mother Kiara Willis, 33, went upstairs in May last year to find Liam unconscious with the cord around his neck. The family tried to cut him down, and attempted to revive him while ambulances came, but Liam was later pronounced dead at the University Hospital of Wales in Cardiff. Ms Willis, who has four other children, said the contraption had only been set up a few days earlier. She recalled being downstairs when Liam's brother Delmi called for her help. She said: 'My 12-year-old screamed “Mum!” and I knew something was wrong. I ran upstairs - he was just dangling there. Inventive: Liam set up the device to suspend a tablet computer on which he could watch films, but it had only been up a few days before he became fatally entangled inside it. 'I tried to get him off and I couldn’t. My 16-year-old got a knife and tried to cut him down. 'We tried to give him mouth to mouth and we were on the phone to the ambulance. It all happened so quickly. Liam was always climbing on things and jumping off them.' Horror: Liam's mother Kiara Willis, pictured, told the inquest of the moment she discovered her son. Coroner David Bowen said: 'I’m satisfied that Liam was a typical nine-year-old full of life and had no appreciation of danger. 'He shared a bedroom with his brother and they had suspended a Heath Robinson-type of contraption which they used to watch videos. 'While it wasn’t being used for that he would put his body through the contraption and use it as a swing. 'I’m satisfied that was what he was doing the moments before he died.' Mr Bowen said the dressing gown cord 'must have twisted in a totally unexpected way with fatal results.' He recorded a verdict of accidental death at the inquest in Newport, South Wales. His father Shane Gardner, 34, wrote a message to Liam on a social network site. He said: 'Why, why why did you have to leave us at such a young age? 'Daddy loves you so much so nothing will ever be the same without you.' After the inquest, Ms Willis said: 'He was a happy-go-lucky little boy. He loved life and playing and winding people up. 'I want parents to be aware of the dangers of bunk beds. I never thought this would happen.'