In 1938 Flavia married Daniel R. Gernatt Sr., and in Collins, New York, the two began a dairy farming enterprise, Dan Gernatt Farms, which in the 1950s was the largest in Erie County.
[1] Gernatt partnered with her husband in breeding and racing Standardbred horses, beginning in 1960.
[3] In 1988, Gernatt and her husband established the Daniel and Flavia Gernatt Family Foundation, a charity which provides financial assistance to organizations and entities in Western New York, mostly in the areas of education, healthcare, Christian-related endeavors, and to those in need or who are homeless.
[1][4][5] In 1992 Gernatt and her husband donated the construction of a new rectory to St. Joseph Parish in Gowanda, where they were active members and benefactors, and where Flavia was a lay eucharistic minister.
[1] She and her late husband have a son, Daniel R. Gernatt Jr., who is currently the chief executive officer of the Gernatt Family of Companies;[8] and two daughters, Patricia Rebmann and Phyllis Ulmer.