Growing up in Western Australia, Leonie was an avid reader from an early age. Her mother vividly recalls her stating "I can read faster with my eyes than you can with your mouth, Mum..." at around the age of six. Her parents and great aunt encouraged her interest in literature, providing her with books of many different genres, and . She began writing during high school, placing in the Western Australian Young Writers Award in 1980, and she fondly remembers several of her English teachers, who encouraged her to write, both fiction and poetry.