The little boy began complaining of stomach pains last week, and was taken to hospital in Bengal, India.
After doctors examined his swollen belly, they decided that he had a tumour, and immediately offered an ultrasound and a CT scan.
However the scans revealed that the little boy did not have a tumour.
Instead, he had a ‘developed’ dead foetus in his abdomen.
Dr Shirshendu Giri, who performed the surgery to remove it, told IBN Live: “The dead embryo which had hands, legs, nails and a partially formed head was removed from the child's body after a long operation.
“The boy is is alright now still under close observation.”
‘Foetus in fetu’ is a condition in which a malformed foetus is found inside the body of its twin.
These foetuses are usually discovered in the abdomen, although some cases have seen it develop in the skull.
It is incredibly rare, affecting only one in five million births.
Stock images used throughout.
It is for this reason that only 200 cases of it happening have ever been reported.