Mbh 1.126.4a

“The Kauravas, then, accompanied by their priest, saluted the Rishis by lowering their heads, and took their seats before them. The citizens also saluting the ascetics and bowing down unto them with touching the ground, took their seats there. Then Bhishma, setting that vast concourse perfectly still, duly worshipped, O king, those ascetics by offering them water to wash their feet with and the customary Arghya. And having done this, he spoke unto them about the sovereignty and the kingdom. Then the oldest of the ascetics with matted locks on head and loins covered with animal skin, stood up, and with the concurrence of the other Rishis, spoke as follows, ‘You all know that that possessor of the sovereignty of the Kurus who was called king Pandu, had, after abandoning the pleasures of the world, repaired hence to dwell on the mountain of a hundred peaks. He adopted the Brahmacharya mode of life, but for some inscrutable purpose the gods have in view, this his eldest son, Yudhishthira, was born there, begotten by Dharma himself. Then that illustrious king obtained from Vayu this other son--the foremost of all mighty men--called Bhima. This other son, begotten upon Kunti by Indra, is Dhananjaya whose achievements will humble all bowmen in the world. Look here again at these tigers among men, mighty in the use of the bow, the twin children begotten upon Madri by the twin Aswins. Leading in righteousness the life of a Vanaprastha in the woods, illustrious Pandu hath thus revived the almost extinct line of his grandfather. The birth, growth, and Vedic studies of these children of Pandu, will, no doubt, give you great pleasure. Steadily adhering to the path of the virtuous and the wise, and leaving behind him these children, Pandu departed hence seventeen days ago.