SB 1.9 - Parvata, Nārada and Dhaumya
Some of the great souls who accompanied Yudhiṣṭhira to see Bhīṣma:
Parvata Muni – a constant companion of Nārada. He was present at the sacrificial ceremony of Janamejaya, son of Parīkṣit. In this sacrifice all the snakes of the world were to be killed. Parvata and Nārada are called Gandharvas also because they can travel in the air singing the glories of the Lord. They observed Draupadī’s svayaṁvara from the air. Mahārāja Sṛñjaya got the benediction of a son by Parvata Muni.
Nārada Muni – In his previous life he was the son of a maidservant but by serving the pure devotees he became enlightened in devotional service. He is the chief sage among the demigods. He is the son and disciple of Brahmā. He initiated Prahlāda, Dhruva and many other devotees including Vyāsadeva. In the Bhāgavatam he instructed Prahlāda while he was still in the womb of his mother, and he instructed Vasudeva as well as Yudhiṣṭhira.
Dhaumya – A great sage who was the royal priest of the Pāṇḍavas. He acted as the priest at the betrothal of Draupadī. He was present even during the exile of the Pāṇḍavas and instructed them how to live incognito for one year. He was also present at the general funeral ceremony performed after the battle of Kurukṣetra. He gave very elaborate religious instructions to Yudhiṣṭhira.