John Hicks Hamer and Elizabeth Thomas, per the Bible Record of John Hicks Hamer, were married "13th September, 1821."Again per the Bible Record, "Elizabeth Hamer, wife of John Hamer, departed this life July 31, 1825 being in her 31st year of her age."
According to the late Flora Janie Hamer Hooker in her compilation, "JOHN HICKS HAMER 1765-1842, His Antecedents, Descendants and Collateral Families 1744-1949," which was privately published for the author, but which is available for viewing on Microfilm from the Mormon Library, "Elizabeth was the daughter of Nathan Thomas of the Hebron Section, South Carolina.She was born April 26, 1795 and is buried in a cemetery near and across the road from the Old Hebron Methodist Church South, about six miles southeast of Bennettsville. S. C."
Elizabeth was the 2nd wife of John Hicks Hamer and you are correct, she and John had two sons, Philip May Hamer (27 April 1812-29 Sept. 1887) and the Rev. Lewis Myers Hamer (27 February 1828-22 April 1907.