Sinclair was opposed to sex outside of marriage and viewed marital relations as necessary only for procreation. He told his first wife Meta that only the birth of a child gave marriage "dignity and meaning". Despite his beliefs, Sinclair had an adulterous affair with Anna Noyes during his marriage to Meta. He wrote a novel about the affair called "Love's Progress", a sequel to "Love's Pilgrimage". It was never published. His wife later had an affair with John Armistead Collier, a theology student from Memphis; they had a son together named Ben.