Aureli (or Aurelia) is named as a child of Oliver B. Hayes and Sarah C. Hightower in the book "The Kith and Kin of Capt. James Leeper and Susan Drake His Wife" - Author: Nell McNish Gambill (pub. 1946). It states - "Aurelia Hayes; born September 5, the year not known; died October 25, 1850; buried in the Hightower Cemetery."
With the dates as they are given on this memorial page, she is also listed in a transcription of the Richard Hightower Cemetery by Sue Owen, Frank R. Owen and Mrs. Joe Bowman that is included in the book "Directory - Williamson County TN Burials, Vol. 1" (pub. 1973).
Aureli was not listed in a Hayes genealogy published in 1884 nor in the family trees included in the book "Belmont Mansion" (pub. 1981). Have not found her in the 1850 census.
Assuming the cemetery transcription information came from a stone, it is no longer standing in the cemetery. Only 4 graves are still marked in the Hightower Cemetery. If Aureli's marker still exists it is probably in the stack of broken stones and slabs at one end of the small cemetery.