A three-year-old girl thrown from an inflatable trampoline on a beach died from a head injury, a post-mortem examination has found.
Witnesses described how people tried to catch Ava-May Littleboy when the inflatable "exploded" on Gorleston beach, Norfolk on Sunday.
Ava-May, who died in hospital, had been at the beach with members of her family.
Her family, from Suffolk, said she could "light up the darkest rooms".
In a statement, they added: "She was not your ordinary little girl. Anyone that met her would not want to forget her."
Norfolk Police said a Home Office post-mortem examination took place on Monday and found Ava-May had died of a head injury, but that further investigation would take place to confirm this.
A police spokesman said the cordon in the area would remain in place while specialists examine the scene and the inflatable play equipment.
Zoe Dye, who was on the beach at the time with her daughter, said: "Literally, it was just screams from everyone on the beach. It was almost like slow motion. [The] poor little girl was in the air.
"No-one could do anything. People were trying their hardest to catch her and she just dropped."
Ava-May's family has set up a fundraising campaign to raise money for a bench to go on the playing field near their home in Somersham.
Speaking to the BBC, her grandmother Angela Littleboy said she "loved to be outside and play".
"She was her own little character, she was cheeky, funny, the best leg-hugger ever," she said.
"She loved everything, loved everybody, everyone was her best friend. She was a beautiful and bright little girl."
Mrs Littleboy added that the family was still "very numb" after Ava-May's death but was "absolutely overwhelmed" by the love and support shown by others.
The online appeal has raised more than £8,000.
Downing Street has described the incident as a "terrible accident and a tragic loss of life".
The Prime Minister's official spokesman said: "The HSE [Health and Safety Executive] are looking into it, they are the right people to do so.
"We need to wait for that investigation to be completed."
In 2016, a seven-year-old girl died when a bouncy castle broke free from its moorings in high winds in Harlow.
Following Ava-May's death, there have been calls for a temporary ban on bouncy castles and inflatables in public areas.
Harlow MP Robert Halfon wants an "urgent investigation" into their regulation.
He said: "There should be a temporary ban on bouncy castles and inflatables in public areas until we can ensure they are safe.
"These are two tragic deaths of two beautiful little children in the space of a few years and there needs to be an urgent investigation in the regulation and inspection regimes.
"You cannot risk a tragedy like this happening again."
After two horrific tragedies, Government need to look at update of regulations and inspection regime and consider a temporary ban on bouncy castles in public areas until we can be sure that they are safe. https://t.co/pjXom7r5DT— Robert Halfon MP (@halfon4harlowMP) July 1, 2018
The owner of the play equipment on Gorleston's Lower Esplanade, Curt Johnson, said: "We are in complete shock and send our deepest condolences to the family.
"We are in bits and totally devastated; we can't sleep, can't eat, feel sick to the core."
Teddy bears and flowers have been left beside the perimeter fence which surrounds the play area.
One message read: "Taken too soon. Thinking of all your family. Such a sad loss. Sleep tight angel."
Supt Roger Wiltshire, of Norfolk Police, said it was too early to speculate whether the hot weather was the cause of the explosion.
"We've got experts from all around the country coming to help us with all aspects of this investigation," he said.
"I'm a dad myself and you just can't imagine what they would be going through.
"You come to a seaside town like Great Yarmouth and Gorleston for a day out... and as a dad, we've spent many hours standing by a bouncy castle watching the kids jump up and down."
The HSE said it would be providing "specialist assistance" to the investigation, which is being led by the police and Great Yarmouth Borough Council.