(755 ILCS 5/4-7) (from Ch. 110 1/2, par. 4-7)
    Sec. 4-7. Revocation - revival.) (a) A will may be revoked only (1) by burning, cancelling, tearing or obliterating it by the testator himself or by some person in his presence and by his direction and consent, (2) by the execution of a later will declaring the revocation, (3) by a later will to the extent that it is inconsistent with the prior will or (4) by the execution of an instrument declaring the revocation and signed and attested in the manner prescribed by this Article for the signing and attestation of a will.
    (b) No will or any part thereof is revoked by any change in the circumstances, condition or marital status of the testator, except that dissolution of marriage or declaration of invalidity of the marriage of the testator revokes every legacy or interest or power of appointment given to or nomination to fiduciary office of the testator's former spouse in a will executed before the entry of the judgment of dissolution of marriage or declaration of invalidity of marriage and the will takes effect in the same manner as if the former spouse had died before the testator.
    (c) A will which is totally revoked in any manner is not revived other than by its re-execution or by an instrument declaring the revival and signed and attested in the manner prescribed by this Article for the signing and attestation of a will. If a will is partially revoked by an instrument which is itself revoked, the revoked part of the will is revived and takes effect as if there had been no revocation.
(Source: P.A. 81-230.)