Subscribe to Crime X+ today. In 2003, Kathleen Folbigg was found guilty for the deaths of four of her children, and sentenced to 25 years in prison, but - Kathleen has always maintained her innocence. Now, 151 scientists are petitioning for her release, saying they believe two of the four children died by natural causes. They will present their evidence in an upcoming inquiry. In the first episode of Mother’s Guilt Jane Hansen goes back to the beginning, and looks into how a mother became known as Australia’s worst female serial killer. We meet Tracy Chapman, Kathleen Folbigg’s oldest friend from school who tells us why she stands by the Kathleen she knows as opposed to the villain painted in the press.