RCW 6.17.030

When a judgment recovered in any court of this state has been assigned, execution may issue in the name of the assignee after the assignment has been recorded in the execution docket by the clerk of the court in which the judgment was recovered. When the person in whose name execution might have issued has died, execution may issue in the name of the executor, administrator or legal representative of such deceased person after letters testamentary or of administration or other sufficient proof has been filed in the cause and recorded in the execution docket by the clerk of the court in which the judgment was entered.