Valmiki Ramayana Bala Kanda Sarga 46 Shloka 13
Original Shlokaयाचितेन सुरश्रेष्ठ तव पित्रा महात्मना। वरो वर्षसहस्रान्ते दत्तो मम सुतं प्रति।।1.46.13।।
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सुरश्रेष्ठ O Excellent among devatas, Indra, याचितेन having been sought, महात्मना by the illustrious, तव your, पित्रा father, वर्षसहस्रान्ते after completion of thousand years, सुतं प्रति about a son, मम to me, वर: boon, दत्त: granted.
"O best of the gods your illustrious father granted me a boon for a son I sought on completion of a thousand years (of penance).