Wis. Stat. § 879.63
Whenever there is reason to believe that the estate of a decedent as set forth in the inventory does not include property which should be included in the estate, and the personal representative has failed to secure the property or to bring an action to secure the property, any person interested may, on behalf of the estate, bring an action in the court in which the estate is being administered to reach the property and make it a part of the estate. If the action is successful, the person interested shall be reimbursed from the estate for the reasonable expenses and attorney fee incurred by the person in the action as approved by the court but not in excess of the value of the property secured for the estate.
Wis. Stat. § 879.63
Bringing an action under this section is not the exclusive remedy of a party challenging an omission from an inventory. In Matter of Estate of Ruediger, 83 Wis. 2d 109, 264 N.W.2d 604 (1978). Deferred marital property under s. 861.02(1) is property subject to administration for all purposes including the payment of claims under s. 879.63. In Matter of Estate of Moccero, 168 Wis. 2d 313, 483 N.W.2d 310 (Ct. App. 1992).