Valmiki Ramayana Ayodhya Kanda Sarga 18 Shloka 8
Original Shlokaचिन्तयामास च तदा रामः पितृहिते रतः। किं स्विदद्यैव नृपतिर्न मां प्रत्यभिनन्दति।।2.18.8।।
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पितृहिते रतः devoted to the wellbeing of his father, रामः Rama, चिन्तयामास reflected, अद्यैव today only, नृपतिः the king, किं स्वित् why is it, माम् me, न प्रत्यभिनन्दति not reciprocating my greeting.
Devoted to his father's wellbeing, Rama reflected, Why does not father reciprocate my greeting (like on other days)?