 The murders took place between 1989 and 1999 and she was exposed when her husband discovered her personal diary, which detailed the killings and contacted the Police.Folbigg was originally sentenced to forty years' imprisonment, with a non-parole period of thirty years, but on appeal this was reduced to thirty years, with a non-parole period of twenty-five years.She maintains her innocence, claiming the four children died from natural causes.