While the Araucana hen is considered to be "more wild" than most chickens, they are good mothers. Once they decide to go broody it is hard to persuade them off the nest.
Putting extra eggs under them once they do set, is well, risky to the fingers. They are active in the defense of the chicks once hatched and can herd the babies quite well. I lose chicks to some of the more aggressive hens every year but not when they are taken care of by an Araucana mother.
Jadeacres