Teancum Petersen-Crofts found not guilty of murder after killing his mother and two siblings 15 Feb, 2021 06:26 PM 3 minutes to read Teancum Vernon Petersen-Crofts, 19, has been found not guilty of murder. Photo / Supplied news.com.au By: Angie Raphael / NCA NewsWire A New Zealand man who killed his mother and two siblings by repeatedly stabbing them has been found not guilty of murder due to unsoundness of mind. Teancum Petersen-Crofts, 21, stood trial in the Western Australia Supreme Court accused of murdering his mother Michelle Petersen, 48, his sister Bella, 15, and half-brother Rua, 8, at their Perth home in July 2018. Michelle Petersen suffered 54 wounds, while Bella and Rua were each stabbed more than 40 times, the court heard.