In 1925 a Chicago hospital found that David Cunningham, a young man from Gary, Indiana, was suffering from arsenic poisoning. He had fallen ill about six weeks earlier, recovered and gone back to work, and then become sick again. He was the fourth son of Anna Cunningham, a widow who had lived in Porter County before Gary, and two of his brothers were already dead. Walter, thirteen, had died on September 26, 1923, of what his death certificate called endocarditis; he had been insured for $300. Charles, nineteen, had died two days later of what was certified as peritonitis; he had been insured for $1,000. Walter's body was among those exhumed and examined.
Held in the Lake County jail, Cunningham first told a newspaper reporter that she might have put some arsenic into David's food by mistake, and denied that she had poisoned anyone in her family on purpose. That night her daughter Mae came to the jail from the family home in Gary, and Cunningham suddenly agreed to talk if Mae were brought before her. She refused to speak in her cell, asked to be moved to another room, had Mae stand in front of her, and told her calmly that she was done with the whole bunch of them and was coming clean. As her daughter screamed at her not to talk, the forty-nine-year-old woman recited the details. The newspapers reported that she confessed to poisoning three of her children, spreading arsenic over their bread, and that she said she had poisoned the ones she loved best.
Later accounts say she admitted killing her husband and four children between 1918 and 1922 to collect insurance, but the contemporary reports name only her sons, date the deaths of Walter and Charles to September 1923, and describe David as having survived. She was tried in Lake County for poisoning one of her sons, convicted in 1925 and sentenced to life in prison. A newspaper report in 1933 described her as the former Porter County woman convicted eight years before of poisoning a son and suspected of poisoning other members of her family to collect insurance. What became of her after that is not known.