Fifth of six children of James Taylor Mellor and his wife Emma, Kathleen was eight years old when her father died, and she was brought up by her mother. Her ambition was to nurse in a children's hospital. When she left school she was still too young to begin training as a nurse, so she went to the Kindergarten Training College, and it was here that her interests remained. She became the first Director of the Lady Gowrie Child Centre, Adelaide (1940-1944), and it was during this time that her first book, Traffic Lights, was written for her children's library corner, and later published. This was a success, and was followed by the publication of some of her other hand-made books. She became the first Pre-School Adviser to the Kindergarten Union of South Australia, a position she held from 1945 to 1970, and was a leader in the development of pre-school education. She wrote thirteen books for young children, four of which were printed as an International Year of the Child project. She also wrote a history of the North Adelaide Baptist Church, and a history of Kindergartens in SA. She was awarded the MBE in 1970.
