Breakfast cereal he launched the Cornflakes brand, which overnight captured a national market. Soon there were forty rival manufacturers in the Battle Creek area. His brother William K. Kellogg (1860–1951) worked for him for many years until, in 1906, he broke away, bought the rights to Cornflakes, and set up the Kellogg Toasted Corn Flake Company. William Kellogg discarded the health food concept, opting for heavy advertising and commercial taste appeal. Later, his signature on every package became the company trademark. The second major innovator in the cereal industry was Charles W. Post, a salesman who was admitted to Kellogg's sanitarium as
Fay Kellogg of women's suffrage. During an address by the English suffragist Mrs. Pankhurst at Carnegie Hall in 1909, Kellogg was the only architect among dozens of professional women seated on the stage. Kellogg owned a farm on Long Island, where she spent six months of the year, and from which she sold eggs year round. She was reclaiming the "waste land" with the intent of eventually retiring there. Kellogg was described as a small, well-dressed woman with blue eyes. She was also athletic, participating in fencing, boxing, wrestling and equestrian activities, as well as playing basketball and golf. Kellogg became ill