Sibling secured Administrator rights WITH Non-Intervention powers, but I never got Waiver to voice my objection. In fact I never received any document

IN WASHINGTON STATE......Mother passed away about 8 months ago. Due to misc issues none of the 4 children filed anything. Mothers WILL disappeared, only the empty envelope of the Will was laying on the counter? Then one of the children filed to become appointed Administrator, BUT ALSO got powers of Non-Intervention. But I never received any documents including the Waiver with option to approve or Object to granting of Non-Intervention powers. How can this be? Seems mistake was made at court house granting these mighty powers with getting constant from Heirs ? Now this sibling with these powers is saying she can do anything she wants in control of the estate and told me she is NOT including me in our mothers estate. I replied in txt saying its my legal right to be included in moms estate she just reply FU. So now seems not only the Non-Intervention powers were granted wrongly, but also seems she is not executing Administrator role correctly?