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Joseph Smith/Polygamy/Plural wives/Sarah Maryetta Kingsley Howe
Sarah Maryetta Kingsley Howe
Joseph Smith's Polygamy: "After Louisa Beaman, Joseph Smith Seeks Almost Exclusively “Eternity Only” Sealings", by Brian C. Hales
Question: What did the husband of Sarah Kingsley know about her sealing to Joseph Smith for eternity?
Sarah was married to non-Mormon John Cleveland, but was sealed to Joseph Smith
Sarah was married to non-Mormon John Cleveland. John was not interested in joining the Church, but was friendly to the Saints.
In the days of Joseph. Mother [Sarah M. Kingsley (Howe)] Cleveland by advice, was sealed to the prophet in Nauvoo but lived with her [non-LDS] husband John Cleveland. 
Sarah wished to go west with the Saints, but Brigham Young advised her to remain with her husband
When the Saints moved west, Sarah wished to go with them, even to the point of leaving her non-LDS husband. Brigham Young advised her to remain with him:
Brigham Young and council...counseled her to stay with her husband as he was a good man, having shown himself kind ever helping those in need, although for some reason his mind was darkened as to the gospel. She obeyed council and stayed with her husband, and was faithful and true to her relation and died a faithful member of the Church of Jesus Christ of Latter Day Saints. 
A biography of Sarah Kingsley may be viewed on Brian and Laura Hales' website "josephsmithspolygamy.org". off-site
- Holograph letter of John L. Smith attached to a letter of the First Presidency dated March 8, 1895, the letter of Smith being written on Feb 27, 1895, to David H. Cannon; copy in D. Michael Quinn Papers—Addition—Uncat WA MS 244 (Accession:19990209-c), Box 1—Card file—Topic: Polygamy, Joseph Smith’s. off-site
- Anon. Biography, CHL. Possibly by August Cleveland Smith quoted in Todd Compton, In Sacred Loneliness: The Plural Wives of Joseph Smith (Salt Lake City: Signature Books, 1997), 283. off-site