He was 22 and she was 15 - young by today's standards, but within marrying age in 1846. Because she was not legally old enough to marry (21 or older), her father personally gave his consent to the county clerk.
Marriage Bond and License
Wm. H. Crawford and Polly Ann Green
Who were they? William H. Crawford and Polly Ann Green. Unfortunately, their marriage would last less than three years. Polly Ann died in 1849, perhaps in childbirth or perhaps of a disease with no known cure at that time. Polly Ann was buried in Piney Fork Cemetery, which tradition says was the site of the last Indian battle in western Kentucky. Her parents, George and Polly Green, both outlived their daughter and are buried next to her. Nearby is Piney Fork Cumberland Presbyterian Church, organized in 1812, the same year church members "erected a log church on the knoll in what is now the cemetery." Polly, indeed, rests in hallowed ground.
Tombstone of Polly Ann Green Crawford 
William H. Crawford was a widower less than two years and then married Sarah J. Dollins in Caldwell County 3 December 1850. He and Sarah made their home in Livingston County and are buried in Hopewell Cemetery in that county.
 Original marriage bond and license 1846, Crittenden County, Kentucky Clerk's Office, Marion, Kentucky.
 Piney Fork Church Historical Committee. The Second History of Piney Fork Cumberland Presbyterian Church, Crittenden Co., Kentucky 1812 - 1992, (n.p., 1992) 2.
 Tombstone of Polly Ann Green Crawford, Piney Fork Cemetery, Crittenden County, Kentucky; photographed 25 January 2017.
 Brenda Joyce Jerome. Caldwell County, Kentucky Marriages 1833 - 1853, (Evansville, IN: Evansville Bindery, 1997) 137.
Published 31 Jan 2017, Western Kentucky Genealogy Blog, http://wkygenealogy.blogspot.com/