Two fairground workers who “put profit before safety” have been convicted of the gross negligence manslaughter of a little girl who died when a bouncy castle blew away with her inside it.

Seven-year-old Summer Grant died after a gust of wind lifted the inflatable from its moorings and sent it “cartwheeling” 300 metres down a hill at an Easter fair in Harlow, Essex, Chelmsford Crown Court heard.

William Thurston, 29, and his wife Shelby Thurston, 26, both denied manslaughter by gross negligence but were found guilty by majority verdict on Wednesday after more than 11 hours of deliberations.

The jury reached majority verdicts of 10 jurors to two.

Shelby and William Thurston were convicted of gross negligence manslaughter (Joe Giddens/PA)
Shelby and William Thurston were convicted of gross negligence manslaughter (Joe Giddens/PA)

The couple, of Whitecross Road, Wilburton, near Ely, Cambridgeshire, were also found guilty of a health and safety offence following the incident on March 26, 2016.

There were gasps and sobs from relatives of the defendants as the verdicts were read out.

Summer’s mother Cara Blackie appeared tearful as she left the courtroom before the hearing had finished, while her father Lee Grant remained in the room.

After the hearing Shelby Thurston left the courtroom in tears, while William Thurston cried as he hugged a family member.

Cara Blackie, Summer's mother, outside court (Joe Giddens/PA)
Cara Blackie, Summer’s mother, outside court (Joe Giddens/PA)

Prosecutors said that the defendants failed to ensure that the bouncy castle was “adequately anchored” to the ground and failed to monitor weather conditions to ensure it was safe to use.

Summer’s father told the trial he turned to see the bouncy castle in the air after he heard a scream, and said “my daughter’s in there”.

He gave chase but could not catch the inflatable, that witnesses described as “cartwheeling in the air, cartwheeling down a hill and only stopping when it hit a fence”.

Summer was rescued from within the bouncy castle and taken to hospital where she died from her injuries.

Summer's father Lee Grant tried in vain to chase the inflatable (Joe Giddens/PA)
Summer’s father Lee Grant tried in vain to chase the inflatable (Joe Giddens/PA)

Her little sister Lily, who was five years old at the time, was also at the fair.

Shelby Thurston had told the trial that as she tried to comfort Lily and her grandmother after the incident, Lily said something that “completely broke my heart”.

“She said ‘I think Summer’s poorly’,” Thurston said.

A yellow Met Office weather warning was in place on the day of the incident, two days before Storm Katie was due to arrive.

William Thurston told the court he felt a “slight sense of disbelief” when he saw the bouncy castle lift “suddenly”.

He described the incident as the “worst thing I’ve ever seen”.

He said he had “no scientific way” of gauging wind speeds, and agreed with his barrister that he had been trained to observe things like “fluttering leaves on trees” to monitor weather conditions.

Candles left by members of the public in memory of Summer (Lauren Hurley/PA)
Candles left by members of the public in memory of Summer (Lauren Hurley/PA)

Judge Mr Justice Garnham, delaying sentencing until a date to be fixed, said: “All options are open and you know that’s sometimes code, but I shall be seriously considering imprisonment, now the defendants know that.”

He ordered that both defendants surrender their passports before they are granted bail, that a surety of £30,000 per defendant is provided, and that they report to Ely police station as part of their bail conditions.

Detective Chief Inspector Danny Stoten of Essex Serious Crime Directorate, who was the senior investigating officer in the case, said Summer’s family were “pleased and relieved” with the guilty verdicts.

He added: “I don’t think it’s quite set in at the moment so they’ve asked to be given some time to come to terms with this result and then they’ll be happy to speak to the media.”

He said: “The Thurstons put profit before safety.

“They had huge weight on their shoulders and that was for the safety of children, other people’s loved ones.

“They put profit first, they’ve ignored the rules and the regulations, they didn’t conduct the checks they should have conducted and sadly Summer’s lost her life.”