Sarah Parker was born in July 1809 in Clavering, a village near Saffron Walden in Essex, England. She grew up in a time when life was often difficult, especially for families with limited financial means. In 1828, she married Richard Chesham, a farmer. Together, they had six sons. This large family put a strain on their finances, making daily life a challenge.

In January 1845, Sarah Chesham faced suspicion when two of her children, Joseph and James, fell ill and died. Symptoms included vomiting and stomach pains. The local doctor claimed they died from cholera, but many in the community thought they had been poisoned. The following year, another child, Solomon Taylor, died after being fed by Sarah. His mother claimed Sarah had prepared the food. A toxicologist examined the body but found no evidence of poisoning. However, later examinations of Joseph and James’s bodies revealed arsenic.

Sarah was first tried for the deaths of her children in March 1847. Despite expectations of a guilty verdict, a jury acquitted her after a brief discussion, stating the prosecution could not prove she had given them poison. She was tried again the next day for Solomon Taylor's death and was acquitted again, this time because it was unclear if he had been poisoned.

Public opinion turned against her. She was called "Sally Arsenic” and was heavily criticized in the press. Many believed she was guilty despite the verdicts. In May 1850, her husband, Richard, died after suffering from tuberculosis. An autopsy showed small amounts of arsenic in his body. During his illness, Sarah had cared for him and insisted on feeding him herself.

After Richard's death, police arrested Sarah. They found a large sack of rice containing visible amounts of arsenic. Sarah was charged with attempted murder since Richard's body did not contain enough arsenic to be fatal. It was argued that she had given him small doses over time. Witnesses testified that Sarah had offered to poison others.

On 25 May 1851, Sarah Chesham was found guilty of attempted murder and hanged. After her execution, some questioned the evidence and fairness of her trials. Critics pointed out that she had no legal representation during her trials, and the jury may have been influenced by the media's portrayal of her. In later years, appeals for a pardon were made, but they were denied due to insufficient evidence to challenge her guilt.