Martha Needle appeared to be a loyal housewife and a loving mother, but she harboured a dark secret. Martha methodically and painstakingly poisoned her entire family a little over a century ago. Drop by deadly drop, one by one, she killed her husband, three daughters, and the brother of her new fiancé, appearing to be loyal to her suffering loved ones as they died at her hands.
Source Materials:
https://www.oldtreasurybuilding.org.au/martha-needle/
https://prov.vic.gov.au/about-us/our-blog/martha-needle
https://blogs.slv.vic.gov.au/such-was-life/martha-needle-melbournes-19th-century-serial-poisoner/
https://australiasdarkheart.weebly.com/martha-needle.html
https://trove.nla.gov.au/newspaper/article/168966386
https://vagrantsandmurderesses.com/record/featured/516/11/409