Devibhagavatapurana 1.4.4

1.4.4

sūta uvāca |
purā sarasvatītīre vyāsaḥ satyavatīsutaḥ |
āśrame kalaviṅkau tu dṛṣṭvā vismayamāgataḥ ||

Sûta said:-- In long-past days, Satyavati's son Vedas Vyâs, while in his own hermitage on the banks of the river Sarasvati, was greatly wondered to see a pair of Châtakas (Sparrows). He saw the pair putting the beak of their young one, just born of the egg, of beautiful body, red mouth, and greasy body. They do not care at all for their own hunger and toil; all they are caring for is to nurture their young one. He said also that the pair are rubbing their bodies over the body and kissing lovingly the mouth of the young one and feeling the highest pleasure. Seeing this wonderful affection of the two sparrows towards their young, Veda Vyâs became very anxious and thought over the following in his mind.