令 + family-relation = honorific for the listener's family member. Pair set:
令郎 (your son),
令爱/
令嫒 (your daughter),
令尊 (your father),
令堂 (your mother),
令兄 (your elder brother). All are formal/written, mostly used in polite letters or by older speakers. The matching humble term for one's own son is
犬子 (quǎnzǐ, "my pup").
