Sumitra was third wife of Dasaratha, the king Ayodhya, and mother of Lakshmana and Shatrughna. Dasaratha married Sumitra, princess of Kashi, as his other wives were childless. She was a highly righteous and had great equanimity of mind. Though younger in age, she had the maturity to advise the senior queen Kausalya when the latter was plunged in sorrow.
She had an optimistic outlook in life and faced any situation with all fortitude. When her son Lakshmana, departed to the forest, along with Rama, on the fourteen-year-exile, she did not lament but deemed that he was doing so for a noble purpose. Her advice to Lakshmana to revere Rama as his father, Sita as his mother and consider the hard life in the forest as comfortable as the royal life in the capital Ayodhya, shows the great character of Sumitra.
During the entire period of fourteen-year exile of Rama to the forest, she remained with his grief-stricken mother Kausalya, comforting her and sustaining her hopes for better days when Rama returned from exile. She presented herself as a foil to Kausalya and Kaikeyi.
When King Dasaratha did not have children from his wives, he urged Rishyashringa Rishi to perform forhim the Putrakameshti Yagna to get progeny. When the divine mantras were chanted and oblations made into the sacrificial fire, a supernatural being emerged out of it with a pot containing a pudding of ambrosia. Dasharatha offered half of the divine Prasad to Kausalya, a quarter to Sumitra, an eighth of what remained to Kaikeyi, and then, on reflection, presented the final eighth to Sumitra. Having received two portions, Sumitra became the mother of twin sons.