Herself

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Old English(see her, self).

wiktionary

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From Middle English. Equivalent to her +‎ -self.

etymonline

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herself (pron.)

emphatic or reflexive form of third person feminine pronoun, Old English hire self; see her (objective case) + self. Originally dative, but since 14c. often treated as genitive, hence her own sweet self, etc. Also compare himself.