(21 April 1913 - 26 April 1961) (her death)
In 1913, Sinclair married Mary Craig Kimbrough (1883–1961), a woman from an elite Greenwood, Mississippi, family who had written articles and a book on Winnie Davis, the daughter of Confederate States of America President Jefferson Davis. He met her when she attended a lecture by him about The Jungle. In the 1920s, they moved to California. They were married until her death in 1961.