I'm trying to understand why there is a difference between the possessive determiner and pronoun for the female gender (her vs hers) but not for the male gender (his is used for both).
"This will be discussed with him and his parents will be informed" and "This will be discussed with her and her parents will be informed" both seem correct, but I'm wondering about the origin of the fact that 'male' gender does not have a distinction whereas the female gender appears to have one, e.g. we would not say "hers parents".
Is there an etymological reason for not using "hers parents", or just a stylistic one (e.g. "hers parents" sounds odd whereas "his parents" doesn't)?