Valmiki Ramayana Bala Kanda Sarga 51 Shloka 18
Original Shlokaप्रजापतिसुतश्चासीत्कुशो नाम महीपति:। कुशस्य पुत्रो बलवान् कुशनाभस्सुधार्मिक:।।1.51.18।।
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प्रजापतिसुत: son of Prajapati, कुशो नाम named Kusa, महीपति: आसीत् there was a king, बलवान् strong, सुधार्मिक: supremely righteous, कुशनाभ: Kusanabha, कुशस्य पुत्र: son of Kusa.
There was a king named Kusa who was the son of Brahma. His son was Kusanabha who was supremely righteous and strong.