Thank you for the suggestions Judy. Their only for certain child to my knowledge is Sarah Jane Highland who married Cornelius Toms. As already mentioned, their marriage record lists her parents as John and Diana (MNU) Highland. Sarah Jane died approximately 1906, but despite numerous searches, I've thus far been unable to locate any death records, notices, or obituaries for her. I've speculated about a possible sibling, Louisa Highland, born @ 1859, who also very conspicuously appears as a young, single female in the same 1880 census record of LaGrange Co, Indiana (same locality, but different page and household from Jane). So far, I've been unable to conclusively link her with Sarah Jane, but it seems likely that they were close relatives given the circumstances.
Trever Whetzel