Lydia Sherman (December 24, 1824 – May 16, 1878), née Danbury, also known as The Derby Poisoner, was an American serial killer. She poisoned eight children in her care (six of which were her own) and her three husbands and was convicted of second-degree murder in 1872. Five years into her sentence, she escaped under the pretext of being sick and got a job as housekeeper to a rich widower in Providence. She was caught and imprisoned again before dying in Wethersfield State Prison on May 16, 1878 from cancer.