William Clayton swears affidavit giving details about firsthand knowledge of plural wives married to Joseph.
William Clayton, Affidavit, February 16, 1874, Affidavits about Celestial Marriage, MS 3423, Church History Library
On the 1st day of May 1843, I officiated in the office of an Elder by marrying Lucy Walker to the Prophet Joseph Smith, at his own residence.
During this period the Prophet took several other wives. Amongst the number I well remember Eliza Partridge, Emily Partridge, Sarah Ann Whitney, Helen Kimball and Flora Woodworth. These all, he acknowledged to me, were his lawful, wedded wives, according to the celestial order. His wife Emma was cognizant of the fact of some, if not all, of these being his wives, and she generally treated them very kindly.