I am Teia Hassey also in search for the bigger half of our Mueller family. My grandma's great-grandparents were Willhelm and Maria Mueller parents of Gottfried Mueller. Gottfried moved with wife's family through Canada to Idaho. His parents and brother moved to Argentina with the rest of the Mueller family. We are still searching for them.
Our family is a member of "Germans from Russian Heritage Society" and also the "American Historical Society of Germans from Russia"