Valmiki Ramayana Ayodhya Kanda Sarga 21 Shloka 12
Original Shlokaप्रोत्साहितोऽयं कैकेय्या स दुष्टो यदि नः पिता। अमित्रभूतो निस्सङ्गं वध्यतां बध्यतामपि।।2.21.12।।
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कैकेय्या by Kaikeyi, प्रोत्साहितः instigated, सः that, दुष्टः vicious, नः पिता our father, अमित्रभूतः यदि becomes enemy, निस्सङ्गं without caring for any relationship, अयम् I will, बध्यताम् shall be imprisoned, वध्यतामपि also shall be slain.
Even if our father instigated by Kaikeyi becomes our enemy, he shall be imprisoned or even slain regardless of our relationship with him.