Obituary for Martha McBride identifies August 1842 as month she was sealed to Joseph.
"Death of Pioneer Woman," Ogden Standard Examiner, November 21, 1901
. . . Mrs. [Martha] Knight became a member of the Relief Society of the church which was organized in Nauvoo. Mr. [Vinson] Knight died July 31, 1842, at Nauvoo and in August, 1842, she was sealed to the Prophet Joseph Smith in the Nauvoo temple. She came to Utah in 1850, settling in Ogden, where she made her home for a number of years.