Valmiki Ramayana Bala Kanda Sarga 77 Shloka 29
Original Shlokaप्रिया तु सीता रामस्य दारा: पितृकृता इति। गुणाद्रूपगुणाच्चापि प्रीतिर्भूयोऽभ्यवर्धत।।1.77.29।।
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सीता Sita, पितृकृता by his father, दारा इति as wife, रामस्य Rama's, प्रिया became beloved, गुणात् because of virtues, रूपगुणाच्चापि by virtue of beauty as well, प्रीति: affection, भूय: again, अभ्यवर्धत developed.
Chosen by his father Sita became Rama's beloved wife with her virtue and beauty his affection for her grew further.