Sofia Maria Ekwall was born on February 18, 1826, as the eldest daughter of Per Ludvig Ekwall, a wealthy estate owner, and grandson of statesman Christopher Retzius Ekwall. In 1844, the family moved to the Attarp manor in Småland, Sweden. Per Ekwall was described as an honest but depressive individual, and his relationship with his family was reportedly strained. Sofia Maria's upbringing was marked by the expectations and constraints of her social class during the 19th century.​

In late May 1845, Per Ekwall fell suddenly ill after consuming a meal prepared by his wife, Hedvig Christina. Although he initially showed signs of recovery, his condition worsened after consuming oat soup and he died on June 5, 1845. Around the same time, the family's maid, Maja Stina Forsberg, and one of the younger Ekwall daughters also became ill; Forsberg died shortly after, while the child recovered. A doctor determined that poisoning was the cause of these illnesses and deaths.​

Investigations revealed that Sofia Maria had procured arsenic, ostensibly to remove stains from a silk dress. Under questioning, she confessed to administering the poison, implicating her mother as an accomplice. However, Hedvig Christina consistently denied involvement and was eventually released due to lack of evidence.​

In 1846, Sofia Maria was convicted of the murders of her father and Maja Stina Forsberg and sentenced to death. Following a plea for clemency, her sentence was commuted to 28 days on bread and water, followed by life imprisonment. She was released in 1876 and lived until her death on July 8, 1897, in Norrköping, Sweden.​