Ellen Devereux (Sewall) Osgood was born on March 10, 1822, in Barnstable, Massachusetts, to Edmund Quincy and Caroline (Ward) Sewall. Edmund Sewall was a Unitarian minister in Scituate, Massachusetts, for seventeen years. In 1842, Ellen met Reverend Joseph Osgood, born on September 23, 1815, to Dr. Joseph Otis and Elizabeth (Fogg) Osgood in Kensington, New Hampshire. They married on May 20, 1844. Rev. Joseph Osgood, like Ellen’s father, was a Unitarian minister, who served fifty-five years as the pastor at the First Unitarian Church of Cohasset. Ellen and Joseph had ten children: Caroline Ward, born in 1845 but died the same year due to accidentally smothering in her bedding when no one was watching; Elizabeth, who married George Lyman Davenport and had George L. Davenport, who maintained this collection; Joseph Otis; Edmund Quincy Sewall; George; Ellen Devereux; Mary Fogg; William Sherburne; Frances Parsons; and Louise Lovett, who helped her sister Elizabeth write the article about their mother and Henry David Thoreau. Ellen died on December 8, 1892 and Joseph died on August 2, 1898.