Charles McWilliam was born on December 26, 1950, in Pasadena, California. Charles married Katie on January 15, 1993, and they had four children: Charles Jr., Rebecca, Amy, and Jamie.

McWilliam was a professional engineer and employed by Application Engineering Company (AEC), Energy Research and Development Administration (ERDA), and the Department of Energy (DOE) in affiliation with the Nevada Test Site.

Katie McWilliam was born on September 6, 1960, in Buffalo, New York. Katie married Charles "Chay" on January 16, 1993, and they had four children: Jamie, Charles "Chay" Jr., Rebecca "Becky," and Amy.

McWilliam obtained a bachelor of science and master of science degree in geology.

McWilliam was a consultant for the Nevada Test Site regarding seismological issues. McWilliam was also previously employed as a business and marketing manager.

Nevada pioneer, engineer, and surveyor John Thomas (J.T.) McWilliams was born in Owen Sound, Ontario, Canada, on December 10, 1863. In 1879, he moved to Detroit, Michigan, before settling in Chicago, Illinois in 1883. While in Chicago, McWilliams studied civil engineering at the University of Chicago, and in 1884 he began surveying for the Northern Pacific Railroad.