In plain words
Nine months passed. On an auspicious day, at a sacred hour when the five elements stood in balance, a son was born to Kausalyā. He was Rāma. Sumitrā gave birth to two sons. They were Lakṣmaṇa and Śatrughna. To Kaikeyī a son was born. He was Bharata. It was precisely because He was one who drew people to Him and gladdened them that Kausalyā's son was named Rāma. Rāma is He who gives delight. Not only this. As one sees a reflection in a mirror, He saw the Ātma in the heart of every single person. In all beings He saw the radiance of the Ātma, like the orb of the moon. That is why He came to be called Rāmacandra.
Sumitrā's children kept crying from the moment they were born; they would not drink milk, they would not sleep. Seeing her children's state, Sumitrā grieved deeply. At a time when no one was about, she went to Vasiṣṭha: “Swami! My children have no bodily ailment, but they have been crying from the moment they were born. What is the reason for this?” she asked. Vasiṣṭha closed his eyes, sank deep in dhyāna, and looked with divine sight. After a while he opened his eyes: “Mother Sumitrā! You are very fortunate; true to your name, you move among all with an equal eye and in friendship. You need not grieve over your sons' state. Do as I tell you. Go to Kausalyā and Kaikeyī, get their permission, and lay Lakṣmaṇa down beside Rāma; lay Śatrughna down beside Bharata. Then they will stop crying and drink their milk, sleep soundly, and be happy in every way,” he said. When Sumitrā went to Kausalyā and Kaikeyī and made this known to them, they were overjoyed: “Sumitrā! Those too are our own children, and these too are our own children. Is it not a joy for us too that all should live together in harmony! So bring Lakṣmaṇa and Śatrughna at once,” they said. Sumitrā brought Lakṣmaṇa and laid him down beside Rāma. She laid Śatrughna down in the cradle where Bharata lay. From that moment the two stopped crying and, kicking their legs and waving their arms in glee, began to crow with joy.