Who is the mother of Pandavas in the Mahabharata? Actually the question should be rephrased as there are two mothers. The Five Pandavas had two mothers. Kunti was the mother of Yudhishtira, Bhima and Arjuna. Madri was the mother of Nakula and Sahadeva.
It is believed that Kunti became the mother of Yudhishtira through the blessings of Yama (Dharmaraja). Bhima was born with the blessings of Vayu (wind god). Arjuna with the blessing of Indra.
Nakula and Sahadeva were born to Madri with the blessings of Ashwini Kumars.
Pandu the husband of Kunti and Madri was cursed by a Yaksha that he will die if he approaches his wife for sexual union. Therefore Kunti who had got the boon from Durvasa to beget children from the God she likes uses the boon and shares the boon with Madri.