Valmiki Ramayana Ayodhya Kanda Sarga 39 Shloka 32
Original Shlokaसीताया वचनं श्रुत्वा कौशल्या हृदयङ्गमम्। शुद्धसत्त्वा मुमोचाश्रु सहसा दुःखहर्षजम्।।2.39.32।।
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कौशल्या Kausalya, हृदयङ्गमम् heartstirring, सीतायाः Sita's, वचनम् words, श्रुत्वा having heard, शुद्धसत्त्वा with purified mind, सहसा instantaneously, दुःखहर्षजम् produced out of joy and grief, अश्रु tears, मुमोच shed.
Listening to the heartstirring words of Sita, Kausalya with her heart so pure burst instantaneously into tears of joy and grief.