Wash. Rev. Code § 11.72.006
After the expiration of the time limited for the filing of claims and before final settlement of the accounts of the personal representative, a partial distribution may be decreed, with notice to interested persons, as the court may direct. Such distribution shall be as conclusive as a decree of final distribution with respect to the estate distributed except to the extent that other distributees and claimants are deprived of the fair share or amount which they would otherwise receive on final distribution. Before a partial distribution is so decreed, the court may require that security be given for the return of the property so distributed to the extent necessary to satisfy any distributees and claimants who may be prejudiced as aforesaid by the distribution. In the event of a request for a partial distribution asked by a person other than the personal representative of the estate, the costs of such proceedings and a reasonable allowance for attorneys fees shall be assessed against the applicant or applicants for the benefit of the estate.
RCW 11.72.006