She was born on October 28, 1855 in Caldwell County, Missouri to John Fletcher Ray and Susan (Hutchins/Hutchings) Ray. She had several siblings. They included sisters Maud Lee, Nancy Frances, and Terisa Ann and brothers William Jason, James W., Jefferson Davis, and Moses Price.
She married John Warren St. John on September 29, 1873 in Christian County, Missouri. Together they had two sons John and James and four daughters, Emma, Edna, Lena, and Nancy.
Mary Jane passed away on June 2, 1913 in Sparta, Christian, Missouri, USA. Her death was attributed to a brain tumor but according to her death certificate, there was no positive diagnosis by a physician.
According to a conversation that I had with my grandmother, Warren St. John was so afraid that due to Mary Jane's death by a brain tumor someone would attempt to dig her remains up to use her for science that as the undertaker was covering her grave at the funeral, he (Warren) tossed the key to the burial vault into the vault so that her remains would be undisturbed.