Valmiki Ramayana Bala Kanda Sarga 20 Shloka 11
Original Shlokaचतुर्णामात्मजानां हि प्रीति:परमिका मम।।1.20.11।। ज्येष्ठं धर्मप्रधानं च न रामं नेतुमर्हसि।
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चतुर्णाम् among the four, आत्मजानाम् sons, मम for me, परमिका great, प्रीति: हि affection indeed, ज्येष्ठम् eldest, धर्मप्रधानम् च with virtue as prime qualification, रामम् Rama, नेतुम् to take, नार्हसि it is not proper.
My love for Rama among all my four sons is supreme.It is not proper for you to take Rama, the eldest son whose prime qualification is his virtue.