Her first book, Sunny Hours of the Child Life of Tom and Mary, received the endorsement of Oliver Wendell Holmes.

[4] Eyster assisted In the purchase of Mount Vernon (George Washington's home) for the U.S.; and served as an officer of the Great Sanitary Commission during the American Civil War.

[5] Eyster's teaching extended to California's Chinese immigrants; she was also a teacher of music, rhetoric and belles lettres in various seminaries; and was a state lecturer on scientific temperance in colleges and public schools.

On her maternal side, she was a granddaughter of Captain George W. Ent, a commander at Fort McHenry in the war of 1812 and a friend of Francis Scott Key.

[7] She was associated with Gail Hamilton in the editing of Wood's Magazine,[6] and was also the editor of the Pacific Ensign, the organ of the State WCTU.

[8] Active in woman suffrage and other movements for the advancement of women, her temperance lectures on the subject of the "House Beautiful and the Man Wonderful" made her well known.

In 1876, the family moved from Harrisburg, Pennsylvania,[5] to San Jose, California, which helped Eyster rally from her depression and regain interest in religious and benevolent work.

In Pennsylvania, the family had been members of the English Lutheran Church, but in San Jose, they became connected with the Presbyterian denomination, and Eyster was linked with some of its enterprises.