Sarah Lincoln, older sister of the future 16th president of the United States, was born 10 February 1807 in Elizabethtown, Kentucky. She was the first-born child of Thomas Lincoln and Nancy Hanks. When Nancy Hanks died in 1818, eleven-year old Sarah had to step up and run the household, consisting of her father, brother, and cousin Dennis Hanks, who was living with them. A little more than a year later she was relieved of much of the responsibility when her father remarried.
Sarah married Aaron Grigsby in Indiana in August of 1826. She died in childbirth on 20 January 1828, just over a year after her marriage. The child was stillborn. 
Ancestry.com : Indiana Marriage Collection, 1800-1941; Online publication - Provo, UT, USA: The Generations Network, Inc., 2005. Original data - Works Progress Administration, comp. Index to Marriage Records Indiana: Indiana Works Progress Administration, 1938-1940.Jordan Dodd, Liahona Research, comp.
It may be possible to confirm family relationships with Sarah by comparing test results with other carriers of her mitochondrial DNA.
However, there are no known mtDNA test-takers in her direct maternal line.
It is likely that these autosomal DNA test-takers will share DNA with Sarah: