Wash. Rev. Code § 11.96A.240
Within thirty days of execution of the agreement by all parties, the special representative may note a hearing for presentation of the written agreement to a court of competent jurisdiction. The special representative shall provide notice of the time and date of the hearing to each party to the agreement whose address is known, unless such notice has been waived. Proof of mailing or delivery of the notice must be filed with the court. At such hearing the court shall review the agreement on behalf of the parties represented by the special representative. The court shall determine whether or not the interests of the represented parties have been adequately represented and protected, and an order declaring the court's determination shall be entered. If the court determines that such interests have not been adequately represented and protected, the agreement shall be declared of no effect.
RCW 11.96A.240