- Father: Samuel Siple b. 22 May 1832, d. 4 Jun 1916
- Mother: Sarah A. Smith b. 17 Sep 1850, d. 4 Jun 1942
- Marriage*: Cosmos Siple married Carrie Ann Waggoner, daughter of William Lough Waggoner and Hannah Siple.
- Birth*: Cosmos Siple was born on 27 September 1878 at Pendleton County, West Virginia.
- Death*: Cosmos Siple died on 22 October 1973 at age 95.
Family: Carrie Ann Waggoner