Dr. Stevenson was the first female member of the American Medical Association, author of several books, and is said to have studied with Thomas Henry Huxley and Charles Darwin.
Sources
The History of Ogle County, Illinois, Containing A History of the County---Its Cities, Towns, etc., A Biographical Directory of Its Citizens, War Records of Its Volunteers in the Late Rebellion, General and Local Statistics, PORTRAITS OF EARLY SETTLERS AND PROMINENT MEN, History of the Northwest, History of Illinois, Map of Ogle County, Constitution of the United States, Miscellaneous Matters, Etc., ILLUSTRATED, Chicago, H. F. Kett & Co., Times Building, 1878, p. 702.
"United States Census, 1850," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:M85N-7NZ : 4 April 2020), Sarah J Stevenson in household of John Stevenson, Honey Creek, Adams, Illinois, United States; citing family 141, NARA microfilm publication M432 (Washington, D.C.: National Archives and Records Administration, n.d.).