Is the expiation for an oath (Kaffarat al-Yamin) obligatory upon a minor or an insane person?

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The expiation for an oath is not obligatory upon a minor or an insane person because it relates to speech, and they lack speech capacity. This contrasts with the expiation for accidental homicide, which relates to action, and their action is established, which necessitates financial guarantee upon them. Actions can mandate obligations that speech cannot, evidenced by the fact that manumission (I'taq) is established through their sexual act (Ihbāl) but not through their declaration of emancipation by word.