No, this may be true of a mued, where he (the owner) pays kofer, wherefore minors are equated with adults, as opposed to a tam, where he does not pay kofer. It is, therefore, written (31) "Or if it gore a son (a minor), or if it gore a daughter (a minor). It ("gore") is extra for purposes of formulating an identity (gezeirah shavah). It is written here (re tam [28]) "gore," and there (re mued) "gore." Just as there, minors are equated with adults, so, here.