We had a hen who did this also. From the time the kittens were born, she would sit on them and keep them warm while the mother was out hunting, and then they'd trade places while the hen ate so the cat could feed her kittens.
This chicken one of the rarest breeds in the world and were only owned by kings and emperors.A true dinosaur on the brink of extinction. They will soon be introduced to the USA. Ladys and gentlemen, meet the Dong Tao Ga Ho!