her sister, Mildred Davidson Austin Smith (1916–1993) invented and commercially sold board games.
She invented the sanitary belt with moisture-proof napkin pocket, which was not used until 30 years after she invented it. The company that first showed interest in her invention rejected it after they discovered that she was an African American woman. In 1957, she was finally able to save up enough money to get her first patent on the sanitary belt.

“One day I was contacted by a company that expressed an interest in marketing my idea. I was so jubilant,” she said in an interview. “I saw houses, cars, and everything about to come my way.” A company rep drove to Kenner’s house in Washington to meet with their prospective client. “Sorry to say, when they found out I was black, their interest dropped. The representative went back to New York and informed me the company was no longer interested.”
During World War II in 1941, Mary found a job with the federal government. She worked for the Census Bureau, and later for the General Accounting Office. She also chaperoned younger women who attended dances at military bases in the Washington, DC, area.
One evening when Mary was chaperoning a dance, she met a soldier, James “Jabbo” Kenner. They fell in love and got married. He was a boxer (hence the name “Jabbo”). They adopted three boys but had no kids of their own. She retired from the government work around the same time, after which she opened a flower shop in the Washington DC area while continuing to invent big and small things.
Between 1956 and 1987 she received five total patents for her household and personal item creations. One of her patents held was one on a back washer that could be mounted on the shower or bathtub wall.
Mary’s third patent in 1976, was that for a special attachment for a walker or a wheelchair that included a hard-surfaced tray and a soft pocket for carrying items. The inspiration for this idea came from