Is the administration (Tadbir) and bequest (Wasiyyah) of property valid for a financially incompetent person (Safiih)?

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The administration (Tadbir) and bequest (Wasiyyah) of property are valid for the financially incompetent person (Safiih). This is because these actions concern his own best interest, representing a means of drawing nearer to Allah Almighty with his wealth after he is independent of it.