Many of us grew up singing the children's nursery rhyme Humpty Dumpty, the story of a giant egg who fell off a wall and cracked.
Just to remind you how it goes: "Humpty Dumpty sat on a wall, Humpty Dumpty had a great fall, all the King's horses and all the King's men couldn't put Humpty together again."
Well, newsflash, Humpty Dumpty may not have been an egg.
The revelation, which has totally rocked social media, came after an author posed the question as to why we automatically assumed the character we've been singing about since childhood was an egg, when there's actually no mention of him being an egg in the words.
"Who decided Humpty Dumpty was an egg?" the user tweeted. "Its not in the lyrics, and deciding he's a giant egg is quite a random leap for someone to make, and everyone else being like, 'yeah, a giant egg on a wall. Of course."
The post seemed to send Twitter into something of a frenzy, with many left shocked that the nursery rhyme perhaps wasn't about about an egg at all.
"This has troubled me for ages! Glad you put it out there," one user wrote.
"I have ALWAYS wondered this," another agreed, while another commented that the tweet had "blown my MIND".
So why did we all assume the lead character in one of our favourite nursery rhymes was an egg?
As many twitter users pointed out in response to the tweet, the first egg-type association was likely made in Lewis Carroll's Alice in Wonderland sequel, when an illustrator depicted the character as an egg.
"I think the first instance of him being an egg is in Through the Looking Glass," one user tweeted. "Which…kind of explains it because that’s supposed to be weird."
Other users shared their own theories about who or what Humpty Dumpty was supposed to be.
"It's believed to be Roundhead propaganda about a Royalist cannon," one explained. "First appearance as an egg was in Through the Looking Glass."
If you think about it, it kind of makes sense to depict the character as an egg-type creature rather than traumatising kids with an image of someone or something upsettingly mangled by a nasty fall.
Other theories include that Humpty Dumpty tells the story of King Richard III and his defeat at the Battle of Bosworth Field in 1485, while another drew parallels with Chinese Mythology.
"Chinese mythology includes a faceless creature called Hun-Dun (渾沌), who – while not explicitly described as egg-shaped – represents primordial chaos or the world egg," one user offered.
Turns out the egg question has previously been considered by comedian Ricky Gervais.
"Ricky Gervais did a whole bit about Humpty Dumpty, including the fact he's portrayed as being an egg in illustrations but not in the text of the nursery rhyme," another Twitter user shared.
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The creepy side of nursery rhymes
Of course, Humpty Dumpty isn't the only nursery rhyme to reveal a potentially darker side.
Dating back hundreds of years, nursery rhymes have long played a huge part in our early development, but behind the sing-song tune, the lyrics in fact tell many dark tales of death, disease and violence.
"Nursery rhymes might sound like cute, simple melodies that are often associated with the smiling faces of infants, but the moment we start to scratch the surface of the words beneath the tune, some of them are downright terrifying," explains Dr Edmund Hurst, lecturer in creative writing at Hull university.
Dr Hurst says many other nursery rhymes also reference some pretty upsetting tales.
"Rock-a-bye Baby paints a picture of a precarious bassinet, perched on a splintering tree branch until it cracks and spills baby all over the forest floor far below (cradle and all!)," he says.
"And in It’s Raining, It’s Pouring, we see the impact of blunt cranial trauma on the poor old man who was snoring."
A similar fate is suffered by little Jack who fell down and broke his crown.
"Of course, Jill comes tumbling after, potentially from slipping on a mixture of a spilled pail of water and the contents of Jack’s skull," he adds.
Then there's the "chopper to chop off your head" in the particularly well-sung Oranges and Lemons, which is frankly quite terrifying.
In order to understand the darker underbelly of so many of the songs we grew up with, Dr Hurst says it is necessary to look at their origins.
"Many of our popular nursery rhymes have their origins between the 16th and 18th century, with early collections found in Tommy Thumb’s Song Book (1744) and Mother Goose’s Melody (1780)," he explains.
"Origins and etymologies are hard to pin down, with widespread variations and a mixture of cultural backgrounds.
"For example Ring-A-Ring o’ Roses has been considered as a reference to The Great Plague ('Ashes, Ashes, we all fall down!') though this interpretation arose post-WW2 and has little basis in the more ancient form of the rhyme."
According to Dr Hurst, while nursery rhymes, much like many of the original Fairy Tales, don’t avoid darker topics, they are often saved from being unsuitable for kids by their child-friendly illustrations, an egg-type character, for example, and their catchy melodies.
"With designs that help language acquisition and early education, they remain an endearing connection between generations of parents and children," he adds.