Valmiki Ramayana Yuddha Kanda Sarga 61 Shloka 26
Original Shlokaविवृद्धःकाञ्चनोवृक्षःफलकालेनिकृत्यते । न नप्तारंस्वकंन्यायंशप्तुमेवंप्रजापते ।।6.61.26।।
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प्रजापते Brahma, विवृद्धः developing, काञ्चनःवृक्षः golden tree, फलकाले at the stage of fruiting, निकृत्यते cutting, स्वकम् by you, नप्तारम् great grandson, एवम् in that way, शप्तुम् son, न न्यायम् not proper.
"Oh Brahma! Cutting a golden tree at the stage of fruiting is not fair. It is not proper for you to curse your great grandson in that way."