Tamer Barnum was born on October 18, 1773, in Kent, Litchfield County, Connecticut. After the British evacuated the area around 1780, her parents, Ebenezer Barnum and Mabel Booth, moved their family to a new farm in Monkton, Vermont, as inferred from their children's birth records. Tamer married her 2nd cousin Elihu Barnum on March 20, 1792, in Monkton, Vermont, in a section that was known as Barnumtown. They had 11 children in 28 years. She died on March 25, 1852, in Monkton, Vermont, having lived a long life of 78 years, and is buried in the Barnumtown Cemetery.
Her children were: Lucy, Laura, Amanda, Eda, Betsy, Russell Ebenezer, Elijah Seth, Abigail, Harlow, Lois and Lewis.