When Birthe Sophia Larsen was born on 30 August 1835, in Farum, Frederiksborg, Denmark, her father, Lars Andreasen, was 32 and her mother, Inger Larsen, was 34. She married Mads Lassen Frederiksen on 1 May 1859, in Copenhagen, Denmark. They were the parents of at least 5 sons and 3 daughters. She lived in Frederiksborg, Denmark in 1845 and Svenstrup, Hornum, Ålborg, Denmark in 1870. She died on 1 June 1918, in Ålborg, Denmark, at the age of 82.