The childminding business became very popular in the late 1800′s. This was a time when safe sex was poor and children born out of wedlock was frowned upon. Known as the “baby farmers era,” unwanted or illegitimate babies were placed with parents desperately wanting children, but couldn’t. But if babies weren’t able find a home, some baby farmers would murder them instead and pocket the money. Knorr being a single mother herself, turned to baby farming as a means of providing an income for her and her daughter. But in time like many others, she would also kill the odd baby to live the high life at the expense of others. While living in Melbourne she had buried a couple of bodies in her back yard, before she moved to Sydney. When the next occupier moved in, a body was discovered in the back garden, straight away this was reported to police. The other body was found not long after, Knorr being the previous tenant, was the number one suspect.
In 1893 detailed evidence against Knorr maintained that she was not only a sex addict but was a deceitful cold blooded extortionist.She was found guilty of three murders, that of two boys and one girl. Her total number of murders was to be around thirteen children. Knorr was hung in Pentridge jail Melbourne Australia on January 15th 1894.