"Thomas S. Monson Named 16th Church President", Newsroom, LDS Church, 4 February 2008
On January 16, 2018, Eyring was announced as the second counselor to the newly reorganized First Presidency with Nelson as president and Dallin H. Oaks as first counselor.
Apostolic seniority is generally understood to include all ordained apostles (including the First Presidency and the Quorum of the Twelve Apostles. Seniority is determined by date of ordination, not by age or other factors. If two apostles are ordained on the same day, the older of the two is typically ordained first. See Succession to the presidency and Heath, Steven H. (Summer 1987). "Notes on Apostolic Succession"(PDF). Dialogue: A Journal of Mormon Thought. 20 (2): 44–56..
