Kathleen Bumbernick was born about 1935 to Henry Joseph Bumbernick and his wife, Catherine A. Warden. In the 1940 Federal Census of Johnstown, Cambria County, Pennsylvania, Kathleen had an older brother, Donald.

Kathleen Bumbernick married Robert Custer.

Henry Bumbernick died in 1972, and Catherine A. Warden Bumbernick died in 1998. They are interred at Grandview Cemetery, Johnstown.