Valmiki Ramayana Ayodhya Kanda Sarga 24 Shloka 23
Original Shlokaयथा मयि तु निष्क्रान्ते पुत्रशोकेन पार्थिवः। श्रमं नावाप्नुयात्किञ्चिदप्रमत्ता तथा कुरु।।2.24.23।।
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मयि me, निष्क्रान्ते having departed to the forest, पार्थिवः king, पुत्रशोकेन with grief for his son, यथा how, किञ्चित् even a little, श्रमम् effort, न अवाप्नुयात् will not obtain, तथा in that way, अप्रमत्ता with attention, कुरु do.
After my departure, you must see that the king is not overpowered by grief for his son and struggles as little as possible.