Philona Mandeville was born around 1832 in New York to Michael Mandeville and Elsie Corey. Her father was a farmer who owned $10,000 of real estate and $1,000 of personal property by 1860. The family moved to Rockford, Illinois, by 1850, and Gilbert attended school there. She married John Gilbert on May 27, 1861, and their daughter Gertrude was born around 1874. The family moved to Fort Wayne, Indiana, sometime in the 1860s. He husband died in 1903, and she passed away on February 8, 1922.