[George Q. Cannon]
The First Presidency had a visit from Sister Susa Young Gates and Sister Zina Young Card. They came for the purpose of laying before us the condition of Sister Zina D. H. Young, physically and mentally. She is really incapable of doing business, her memory being so defective. It was decided by the First Presidency that her daughter Zina should act as her private secretary, and a letter was addressed to Sister Young and her Counselors informing them that we had made this appointment, and another letter was addressed to Sister Zina Young Card asking her to act in that capacity.
[Source: The Journal of George Q. Cannon, Church Historian's Press, https://churchhistorianspress.org/george-q-cannon]