With her live-in partner Ken Knight, Barbara had four additional children, including a pair of twin girls born in 1955 in Tenterfield, New South Wales. In 1959, when Katherine was four, her mother's husband, Jack Roughan, died.
The two boys who had lived with him moved in with Barbara and Ken.
Barbara's great-grandmother was apparently an Indigenous Australian from the Moree area who had married an Irishman.
She was proud of this fact and liked to think of her own family as Aboriginal.
This was kept a family secret, as there was considerable racism in the area at the time, and this was a source of tension for the children.
Apart from her twin, the only person whom Knight was close to was her uncle, Oscar Knight, who was a champion horseman.
Knight was arrested and again taken to St Elmo's Hospital, but, apparently recovered, signed herself out the following day.A few days later, Knight slashed the face of a woman with one of her knives and demanded she drive her to Queensland to find Kellett.The woman escaped after they stopped at a service station, but by the time police arrived, Knight had taken a young boy hostage and was threatening him with the knife.Barbara and her lover, Ken Knight, were forced to leave Aberdeen, and moved to Moree, New South Wales.None of her four sons went with her; the two older boys continued to reside with their father, while the two younger sons were sent to be raised by an aunt in Sydney.In May 1976, shortly after the birth of their first child, Melissa Ann, Kellett left her for another woman and moved to Queensland, apparently unable to cope with Knight's possessive, violent behaviour.The next day, Knight was seen pushing her new baby in a pram down the main street, violently throwing the pram from side to side.In fear for his life, Kellett fled before collapsing in a neighbour's house, and he was later treated for a severely fractured skull.Police wanted to charge her, but Knight was now on her best behaviour and talked Kellett into dropping the charges.Four sons were born to the couple before Barbara began an adulterous relationship with Ken Knight, a friend and co-worker of her husband.Both of the families (Rougan and Knight) were well-known in the conservative rural town (population 1,800 in 2016), and the affair caused a major scandal.