The criminal Mary Ann died at the age of 40. Here is all you want to know, and more!
Biography - A Short Wiki
British criminal who was hanged for murdering her children and who may have poisoned as many as twenty-one people in total.
She was married three times and had close to a dozen children. All of her children, her husbands, her lover, her mother, and several children under her care died (most under mysterious circumstances).