Death date for Rebecca Clevenger Allen does not seem to be correct. Research shows Rebecca Clevenger Allen died 26 March 1848 not 26 March 1818. Father of Isaac Allen was Reuben Allen, Mother of Isaac Allen was Else Clevenger.
A Daughter of Isaac Allen was Sycha Allen who married Moses Isaac McCoy. Sycha died after the birth of her only child James Isaac McCoy in 1858 and is believed by information provided by family, to also be buried in the Old Allen Cemetery with her father Isaac Allen.
Reuben A. Allen #17652038 a son of Isaac Allen is also buried in the Old Allen Cemetery.