यवीयान् भ्राता he is your younger brother, एषः वानरः this monkey, ते to you, लालनीयः हि deserves your protection, तत्र there, सन् वा इहस्थो वा whether he is here(at kishkinda) or there (at Rishyamuka), सर्वथा all means, ते your, बन्धुरेव relation.

'This monkey is your younger brother and, therefore, deserves your protection. Whether he is here or there, he is your brother.