One day when her children and the first consort's children were quarrelling, she naturally took sides with her children, and cursed Yama to become a Chandala and Yami to run away from the house.
Thus Yama, the Lord of Hell, became an outcast, and Yami or Yamuna became a running river.
The husband Lord Surya got suspicious since no mother would curse her own children, and so he found out thedeception after inquiry.
Lord Surya discovered the original abode of his consort, and went to her to bring about a compromise and reconciliation.
After the reconciliation, they brought out a set of twins namely the Aswins who are the divine physicians. Such is the legendary story of Chaya.