The stuff of nightmare-inducing horror stories, sent in by Katie B.

Defined on Wikipedia.

“Fetus in fetu (or fœtus in fœtu) is a developmental abnormality in which a fetus gets enveloped inside its twin and an entire living organ system with torso and limbs can develop inside the host.^[1] The abnormality occurs in 1 in 500,000 live births.”

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Reported by ABC News.

“”He just put his hand inside and he said there are a lot of bones inside,” she said. “First, one limb came out, then another limb came out. Then some part of genitalia, then some part of hair, some limbs, jaws, limbs, hair.”"

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