In plain words
One day Daśaratha, Romapāda and Sumantra, the three together, went to Ṛṣyaśṛṅga. At Daśaratha's wish, Ṛṣyaśṛṅga came to Ayodhyā and had Daśaratha perform the Putrakāmeṣṭi sacrifice. As the sacrifice went on, a man of great radiance came out from the midst of the flames and handed Vasiṣṭha a vessel of pāyasa. He gave it to Daśaratha and said it should be shared equally among his three wives. The Kamba Rāmāyaṇa has described this in one way, the Tulasī Rāmāyaṇa in another, and the Vālmīki Rāmāyaṇa in yet another. Daśaratha poured that pāyasa equally into three cups for his three wives. Whether in that age or in this, an equal eye towards all is of the first importance for every person. “Take your ceremonial bath and come, and after you have received the blessings of the great sage Ṛṣyaśṛṅga, you must eat this pāyasa,” he told them.
Sumitrā took her ceremonial bath, went up to the upper terrace of the palace, and sat drying her hair. She set the cup of pāyasa down right beside her. After a little while the maids came and told her that King Daśaratha was calling. Before Sumitrā could tie up her hair and go to take the cup, a kite came from somewhere and snatched the cup away. Sumitrā was stunned. “Daśaratha, my husband, may well be angry! What will Vasiṣṭha say! I may have to fall under Ṛṣyaśṛṅga's curse!”: she began to fret, turning it over every way. At once she ran to Kausalyā and Kaikeyī and told them what had happened. In those days even co-wives lived in close affection, like children of one mother. Kausalyā: “Little sister! Do not grieve,” she said, went inside, brought back a cup just like it, and poured half of her own pāyasa into it. Kaikā too did the same. The three of them went happily to the shrine room and partook of the pāyasa. “My co-wives cared for me and helped me. How fortunate I am!”: Sumitrā was overjoyed.