令 + a kin term is the polite way to speak of the listener's family: 令尊 your father, 令堂 your mother, 令兄 your elder brother, 令弟 your younger brother, 令郎 your son, 令爱 your daughter. All are formal and mostly written, or used by older speakers.
mistakes
令兄 already means 'your', so 你的令兄 is redundant, and using it of your own brother is a blunder. For your own elder brother the humble word is 家兄.
