Valmiki Ramayana Bala Kanda Sarga 25 Shloka 6
Original Shlokaददौ नागसहस्रस्य बलं चास्या: पितामह:। नत्वेव पुत्रं यक्षाय ददौ ब्रह्मा महायशा:।।1.25.6।।
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पितामह: lord Brahma, अस्या: for her, नागसहस्रस्य thousand elephants, बलम् strength, ददौ granted, महायशा: that illustrious, ब्रह्मा lord Brahma, यक्षाय for that yaksha, पुत्रं तु son, न ददौ did not bestow.
The illustrious grandsire Brahma granted her the strength of a thousand elephants, but did not bestow a son on the yaksha.