Valmiki Ramayana Sundara Kanda Sarga 36 Shloka 44
Original Shlokaअनिद्रस्सततं रामस्सुप्तोऽपि च नरोत्तमः। सीतेति मधुरां वाणीं व्याहरन्प्रतिबुध्यते।।5.36.44।।
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रामः Rama, सततम् always, अनिद्रः he does not sleep, नरोत्तमः best of men, सुप्तोऽपि even if he sleeps, सीतेति calling out 'Sita', मधुराम् sweet, वाणीम् voice, व्याहरन् uttering, प्रतिबुध्यते he wakes up.
"Rama, the best of men never goes to sleep and even if he drops off to sleep he mutters 'Sita, Sita' in a sweet voice in his sleep.