जन्मप्रभृति right from birth, राघवः Rama, जनन्याम् with regard to his mother, कौशल्यायाम् in Kausalya, सदा always, युक्तः devoted, यथा how, वर्तते is conducting himself, अस्मासु in all of us, तथैव in the same way, वर्तते is conducting.

Rama conducted himself towards us in the same way as he did towards his mother Kausalya right from the begining.