The legend of the green children of Woolpit concerns two children of unusual skin colour who reportedly appeared in the village of Woolpit in Suffolk, England, sometime in the 12th century, perhaps during the reign of King Stephen (r. 1135–1154). The children, found to be brother and sister, were of generally normal appearance except for the green colour of their skin. They spoke in an unknown language and would eat only raw broad beans
Whatever the actual explanation for the green children, it is important to remember that everything written about in Medieval Europe (Iberia excluded obviously) was written through a Christian lens, often to teach Christian moral lessons, truth be damned.
A notable example is medieval bestiaries, books that list animals that get mocked for including mythical beasts like unicorns and dragons without understanding that the point wasn’t to teach about animals, it was to teach what Christian lessons can be learned from animals. It didn’t matter whether or not unicorns existed, it mattered what unicorns could teach everyone about Christ.
As this article says: