Valmiki Ramayana Ayodhya Kanda Sarga 43 Shloka 18
Original Shlokaसाहं गौरिव सिंहेन विवत्सा वत्सला कृता। कैकेय्या पुरुषव्याघ्र बालवत्सेव गौर्बलात्।।2.43.18।।
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पुरुषव्य्राघ्र O tiger among men, बालवत्सा young calf, गौरिव like cow, वत्सला having affection in the calf, सा अहम् I, कैकेय्या by Kaikeyi, सिंहेन by lion, गौरिव like cow, बलात् forcibly, विवत्सा separated from the calf, कृता is rendered.
O best of men I have been forcibly separated from my affectionate son by Kaikeyi just like a cow from its calf by a lion.