When Isabella Dorinda Coulter was born on 15 May 1875, in Gore, Argenteuil, Quebec, Canada, her father, Henry Sproule Coulter, was 27 and her mother, Rachel Moore, was 21. She married Oscar Lewis McCullough on 20 July 1897, in Morden, Manitoba, Canada. They were the parents of at least 1 son and 1 daughter. She lived in Selkirk, Manitoba, Canada in 1891. She died on 28 May 1958, in Pasadena, Los Angeles, California, United States, at the age of 83, and was buried in Pasadena, Los Angeles, California, United States.