Royal National Lifeboat Institution (RNLI), a UK-based charity which saves lives at sea was confronted with what must have been one of the most extraordinary instances of ingratitude they've ever encountered.

Essentially, the parents of a young girl the RNLI had saved, brazenly sent them a £7 bill for damaging the child's inflatable lilo - as part of the £7,000 rescue mission.

The unnamed girl drifted out to sea off the coast of Porthleven, in Cornwall while floating on the lilo. And so, the costly rescue mission was launched to bring her back to safety.

According to the President of the RNLI branch, Mike Carter, a rescue helicopter was used to save the child.

[[imagecaption|| Credit: Getty]]

A crew member even jumped into the water to retrieve her, leaving the lilo behind - the lilo being deemed. After their brave efforts, however, they were horrified to receive the bill for £7.

Speaking to Bristol Live, Carter explained:

"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 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."

He also added that his commanding officer responded to the parents, saying that they would pay for the replacement of their daughter's lilo in exchange for the £7,000 helicopter rescue.

"Two weeks later the commanding officer (CO) of 771 received a request to pay an invoice for £7 the cost of the lilo," Carter explained. "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."

Evidently, the parents didn't have a leg to stand on...

Parents send coastguards $8.50 bill for a lilo after their child is rescued in a $8,500 helicopter operation