Mbh 12.30.2a

"'Krishna said, "I will recite to thee, O king, the facts as they happened. There are two Rishis, the foremost ones in the world, named Narada and Parvata. Narada is the maternal uncle and Parvata is his sister's son. With cheerful hearts, the uncle Narada and the nephew Parvata had, in days of old, O king, left heaven for a pleasant ramble on earth for tasting clarified butter and rice. Both of them, possessed of great ascetic merit, wandered over the earth, subsisting on food taken by human beings. Filled with joy and entertaining great affection for each other, they entered into a compact that, whatever wish, good or bad, would be entertained by one should be disclosed to the other, but on the event of one of them acting otherwise, he should be subject to the other's curse. Agreeing to that understanding, those two great Rishis, adored of all the worlds, repaired to king Srinjaya, the son of Sitya and said unto him, 'We two, for thy good, shall dwell with thee for a few days. O lord of earth, do thou attend to all our wants duly.' The king, saying, 'So be it,' set himself to attend upon them hospitably. After a while, one day, the king filled with joy, introduced to those illustrious ascetics his daughter of the fairest complexion, saying, 'This my daughter will wait upon you both. Bright as the filaments of the lotus, she is beautiful and of faultless limbs, accomplished and of sweet manners, and is called Sukumari by name.' 'Very well,' said the Rishis in reply, upon which the king directed his daughter, telling her, 'O child, attend upon these two Brahmanas as thou wouldst upon the gods or thy sire.' The virtuous princess, saying, 'So be it' began to attend upon them in obedience to her father's behest. Her dutiful services and her unrivalled beauty very soon inspired Narada with a tender flame towards her. That tender sentiment began to grow in the heart of the illustrious saint like the moon gradually waxing on the accession of the lighted fortnight.