President Lorenzo Snow said the question of the seniority of Joseph F. Smith or Brigham Young in the Council of the Apostles was one of moment and must be decided.
It was determined unanimously that Joseph F. Smith was the senior, he having been sustained by the Apostles and church and ordained and set apart as a member of the Council of the Apostles. Brigham had been ordained an apostle when a boy by his Father and taken in to the Council of the Apostles some years later by setting apart and the vote of the Twelve and Saints.
The President requested us to hand to him two names each to fill the vacancy in the Twelve. ...
[Jean Bickmore White (editor), Church, State, and Politics: The Diaries of John Henry Smith, Signature Books in association with Smith Research Associates, Salt Lake City, 1990, http://bit.ly/johnhenrysmith]