Iowa Code § 633.427
If a contingent claim has been filed and allowed against an estate and all the assets of the estate have been distributed, and the claim becomes absolute, the creditor has the right to recover on the claim against those distributees whose distributive shares have been increased because the amount of the claim as finally determined was not paid prior to final distribution, if an action for recovery is commenced within four months after the claim becomes absolute. Such distributees are jointly and severally liable, but a distributee is not liable for an amount exceeding the amount of the estate or fund so distributed to that distributee. If more than one distributee is liable to the creditor, the creditor shall make parties to the action all such distributees who can be reached by process. By its judgment, the court shall determine the amount of the liability of each of the distributees as between themselves, but if any distributee is insolvent or unable to pay that distributee's proportion, or is beyond the reach of process, the others, to the extent of their respective liabilities, are nevertheless liable to the creditor for the whole amount of the creditor's debt. If any person liable for the debt fails to pay that person's just proportion to the creditors, the person is liable to indemnify all who, by reason of the failure, have paid more than their just proportion of the debt, the indemnity to be recovered in the same action or in separate actions.
Iowa Code § 633.427
84 Acts, ch 1080, §11