Martha Rendell killed three of her stepchildren in Perth over fourteen months by painting hydrochloric acid on their throats, and was the last woman hanged in Western Australia.
She was born in 1871 and was living with Thomas Morris and his children as his de facto wife. Annie Morris, seven, died on July 28, 1907; Olive, five, on October 6, 1907; and Arthur, fourteen, on October 6, 1908. She swabbed their throats with spirits of salts, telling them and the attending doctors that she was treating diphtheria. The children's deaths were certified as natural at the time.
A surviving child ran away and told his mother he believed he was next, which prompted the exhumations that established the cause. She was arrested in July 1909, convicted, and hanged at Fremantle Prison on October 6, 1909: the third anniversary, to the day, of Olive's death. She was one of only a handful of women executed in Australia.