Marshall was born in Johnson City, Tennessee.[1][2] She was the daughter of the Reverend John Ambrose Wood and Leonora Whitaker Wood.[1] From the age of nine until her graduation from high school, Marshall was raised in Keyser, West Virginia,[1] where her father served as pastor of a Presbyterian church from 1924 to 1942.[1]While a junior at Agnes Scott College, she met Peter Marshall, marrying him in 1936.[1] The couple moved to Washington, DC, where her husband served as pastor of the New York Avenue Presbyterian Church and Chaplain of the United States Senate.In 1940, Marshall contracted tuberculosis,[1] for which at that time there was no antibiotic treatment. She spent nearly three years recovering from the illness.[1] Her husband died in 1949 of a heart attack, leaving her to care for their 9-year-old son, Peter John Marshall. He later also became a minister and author.Marshall wrote a biography of her husband, A Man Called Peter, published in 1951. It became a nationwide success and was adapted as a film of the same name, released in 1955. Her success encouraged her to keep writing.Marshall wrote or edited more than 30 books, which have sold over 16 million copies.[citation needed] They include edited collections of Peter Marshall's sermons and prayers, and her own inspirational writings. Her most successful books were A Man Called Peter (1951); and her novel, Christy (1967), which was inspired by the story of her mother's time in the mountains teaching the impoverished children of Appalachia. Christy was adapted as a CBS television series, starring Kellie Martin, beginning in 1994.In 1959, Marshall married Leonard LeSourd,[1] who was the editor of Guideposts Magazine for 28 years. Together they founded a book imprint, Chosen Books.[citation needed] They had three children, Linda, Chester and Jeffery.[3]Marshall died on March 18, 1983 at the age of 68. She was buried alongside her first husband.