Mary "Mollie" Massie was born in Savannah, Missouri, on 7 July 1854. She was the daughter of John Colin and Tabitha Purnell Gresham. Both parents were born in Kentucky. She married John S. O’Brian on 4 January 1882 in Washington County. Mollie’s father was a merchant in Fayetteville from 1860-1870, died in 1891, and is buried in Evergreen Cemetery in Fayetteville. Mollie had two brothers who were physicians; Fredrick O. Massey was a medical doctor and practiced in Huntsville, Madison County, Arkansas, 1880-1900, and her brother James B. Massie practiced in Harris County, Texas. Her brother John Jr. was an undertaker in Fayetteville.