Mary and her sister Mildred patented many practical inventions. They didn’t have technical education, but they were both exceptional at spotting ways to make peoples’ lives better. Together, they invented the sanitary belt. Later, Mary invented the moisture-resistant pocket for the belt. While disabled from multiple sclerosis, Mary went on to invent the walker and the toilet-tissue holder. Mildred Davidson Austin Smith also grew up to patent a board game, Family Treedition, in the 1980s.
In 1976 Kenner patented an attachment for a walker or wheelchair that included a hard-surfaced tray and a soft pocket for carrying items. Kenner also invented a toilet paper holder that she patented. Her final patent, granted on September 29, 1987, was for a mounted back washer and massager.
Kenner never received any awards or formal recognition for her work. However, her inventions and contributions helped pave the way for subsequent innovations. Kenner still holds the record for the greatest number of patents awarded a Black woman by the U.S. government.