Many kids love Kinder Surprise eggs. Chocolate and a toy in one, what more could you ask for?
If you've somehow made it through life without trying one, the delicious sweet treat is a hollow milk chocolate egg with an inner layer of milk-flavoured cream.
Inside the egg is a little yellow plastic capsule which contains a toy - your surprise.
But, prepare to have your mind blown.
Sullivan Poulter took to the Children of the 1980s Facebook page to share his discovery and other people can't believe it.
He shared a picture that reads: "I was today years old when I realised".
He found out that the yellow toy capsule is meant to be the yolk inside the egg.
And it turns out thousands of others didn't know either, as it received 3,500 likes, 20,000 shares and hundreds of comments.
One person said: "Well I never, neither did I and it's so obvious now you point it out".
Another revealed: "Really and the white chocolate is the egg white".
And a third said: "mind officially blown!!!!!!".
"OMG I never knew that", a fourth commented.
One woman also said: "45, who knew??? Apparently you're never too old to learn something new!!"
Kinder chocolate was created by Michele Ferrero, the son of a chocolatier, in Italy in 1968.
Six years later the team came up with the Kinder Surprise egg, with the idea of giving kids "the joy of Easter traditions all year round".
Originally each toy was moulded and painted by hand, with 100 different toys made to fill them each year.
In 1975 they introduced Kinder chocolate with cereals, and they arrived in the UK the following year.
And then of course came the Kinder Bueno - which now also comes in white chocolate - which arrived in the UK in 2001.