The four surviving children of William Riley and Lucinda Pedigo Mendenhall as listed on the 1880 census.
Cornelius Loy and his wife lived in Washington Township, Hendricks County, Indiana, close to the Guilford Township line. The Loys owned nearly 500 acres of land in 1865. Lydia Ann (Aunt Anna) lived with the Loys and married one of their sons A.(mos) D.. Mailing address, P.O Box, Bridgeport, Marion County, Indiana. Lydia Ann is listed as “House Keeper” on the 1880 census. (If you are an ardent genealogy freak and use Pilot Search (an Ancestry web site) to look at the 1880 census you will find Cornelius Loy listed as Cornelius COY.)
Ida lived with the family of Eli W. Parnell in the same vicinity of Washington Township. Eli’s wife, Mrs. Mary A. Loy Parnell, was the daughter of Cornelius and sister to Amos. Ida is listed on the 1880 census as J, Ida Mendinghaul her sister is listed as Annie Mendinghaul (at least on the Ancestry Pilot Search transcription, Eli W. Parnell is listed as PARNLL.). Ida is listed as a “Servant“ on this census. Mailing address, P.O. Box, Bridgeport, Marion County, Indiana.
Biographies of Washington Township from "Atlas of Hendricks Co Indiana" (1878: J.H. Beers & Co., Chicago)

Mary E.(llen) is listed on the 1880 census as “Niece” living in the household of Daniel R. and Sarah E. (Mendenhall) Jones in Earlham, Madison County, Iowa. Sarah E. Mendenhall Jones was the sister of William Riley Mendenhall. There were no other children listed in this household in 1880.

James E.(dwin) Mendenhall is listed on the 1880 census living in the household of David Hayworth in Liberty Township, Howard County, Indiana. He is listed as “Other” in relationship to the head of the household. David Hayworth was the brother of Phoebe Rebecca Haworth who was the mother of William Riley Mendenhall. The Haworth Association of America lists James’ death date as December 23, 1891.