The RNLI has revealed family members of a stranded girl billed them £7 for a lilo that was damaged in her rescue.
Mike Carter, president of a RNLI branch, said coastguard members took to a rescue helicopter to save the girl who was in a precarious situation.
A member of the crew jumped into the water to save the girl, but left her inflatable lilo in the water off Porthleven, Cornwall.
But the rescuers were later stunned to be presented with a bill for £7 - the cost of the lilo - from the parents of the girl they had saved.
Mike said: "A family visiting Porthleven purchased a lilo from a local shop and went to the beach.
"There was an off-shore wind and the parents immediately experienced their child waving goodbye as the lilo went further and further out.
"The coastguard scrambled the SAR helicopter which was soon on scene.
"The diver jumped from the the helicopter and saved the child. He instantly put a knife through the lilo to save any further drifting and they were both winched to safety."
Mike said that after receiving the invoice, the rescuer replied saying they would happily pay - if the family paid for the cost of launching the helicopter.
He added: "Two weeks later the commanding officer of 771 received a request to pay an invoice for £7 the cost of the lilo.
"The CO wrote replying, 'I will be happy to pay your invoice on receipt of payment for the helicopter rescue £7,000.' No response was received."
Mike said that inflatables in the sea pose a constant threat, and only last week the Maritime and Coastguard Agency posted a similar warning.
They said: "Inflatable unicorns, watermelons, dinosaurs, you name it, we've seen it.
"Keep your floating friends for the pool. They may pose well for Insta, but they can also pose a danger when up against strong currents and wind, sweeping you out to sea.
"Remember, supervise kids and call £999Coastguard if you spot an inflatable drifting at sea or yours gets blown away."