Okla. Stat. tit. 58 § 632.2
In all cases of administration of estates of deceased persons in this state, where the final decrees have been entered prior to January 1, 1951, and which said final decrees are, or may be, defective or invalid by reason of any failure to make, or any defect in, the final account, or in the petition for distribution and determination of heirship, or in the order setting the same for hearing, or in the notice of hearing thereon, said final decrees are hereby validated; provided, however, this act shall not apply to any case wherein action is instituted and maintained to modify or vacate such final decree prior to January 1, 1956, and provided, further, that the above shall not apply to insane persons, incompetents, or to any person laboring under legal disability.
Okla. Stat. tit. 58, § 632.2