Mahabharata
Kunti wants to fulfil her maternal expectations, but she has no man. She recollects the moment when her first son Karna was conceived from an arcane mantra which had given her once. Surya, the Sun God, appeared to her then. Thus, Kunti remembers her secret mantra and gives birth to the three sons – Yudhistra, Bhima and Arjuna. Yudhisthira’s father was god Yama, Bhima’s father was god Vayu, and Arjuna's father was Indra.