Valmiki Ramayana Bala Kanda Sarga 46 Shloka 1
Original Shlokaहतेषु तेषु पुत्रेषु दिति: परमदु:खिता। मारीचं काश्यपं राम भर्तारमिदमब्रवीत्।।1.46.1।।
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राम O Rama, तेषु पुत्रेषु when those sons, हतेषु were killed, दिति: Diti, परमदु:खिता afflicted with great grief, भर्तारम् husband, मारीचम् Maricha, काश्यपम् Kasyapas's son, इदम् अब्रवीत् spoke these words.
"O Rama! afflicted with great grief when her sons were killed, Diti said to her husband Kasyapa, son of Maricha: Diti undergoes mortifications for the birth of a son with the consent of Kasyapa-- Indra serves her on an occasion when she was impure enters her womb and severes the embryo into seven parts.