Fetus removed from a baby's brain 

A rare and unusual case was reported in China, where doctors surgically removed a malformed twin from the brain of a 1-year-old girl.

The little girl had shown signs of developmental delays and had an unusually large head, leading to the discovery. The mass was actually a partially formed twin, with bones like a spine, arms, and even finger-like buds.

This rare condition, known as fetus-in-fetu, happens in about 1 in 500,000 births, where one twin grows inside the other.

Fetus-in-fetu is often mistaken for a type of tumor, but it can be identified by the presence of actual body parts.

While most cases involve the mass growing in the abdomen, it's incredibly rare for it to be found in the brain. Fewer than 200 cases have been documented worldwide, and this adds to the small number of cases where the twin developed in such an unusual location.