Valmiki Ramayana Ayodhya Kanda Sarga 8 Shloka 18
Original Shlokaयथा मे भरतो मान्यस्तथा भूयोऽपि राघवः। कौशल्यातोऽतिरिक्तं च सोऽनुशुश्रूषते हि माम्।।2.8.18।।
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मे to me, भरत: Bharata, यथा as, मान्य: worthy of consideration, राघव: son of the Raghus (Rama), तथा is so, भूय: अपि more so, स: he, माम् me, कौशल्यात: more than Kausalya, अतिरिक्तम् more, अनुशुश्रूषते हि is serving me.
For me, if Bharata is worthy of consideration Rama is worthier. He serves me even more (scrupulously) than he does Kausalya.