Rita Mabel Larkin was born on April 17, 1779, in Port Jackson, New South Wales, to Thomas Larkin, a skilled carpenter, and Mary (née Saunders), a dedicated homemaker. The family relocated to the fledgling settlement of Hobart Town, Van Diemen's Land, when Rita was still a child. Rita was the middle child among five siblings, with two older brothers, John and William, and two younger sisters, Alice and Edith.

From an early age, Rita exhibited an insatiable curiosity about the natural world. She spent countless hours wandering the surrounding forests, collecting unusual plants, rocks, and insects, and developing a keen interest in the peculiar and unexplained. This fascination stayed with her throughout her life, shaping her eccentric personality.

Despite the limited educational opportunities in the small settlement, Rita learned to read and write under the guidance of a kindly neighbour, Mrs. Abigail Saunders, who ran a small informal school. Rita's love for learning, particularly about history and natural sciences, flourished under Mrs. Saunder's tutelage.

As a young woman, Rita assisted her mother with household duties and helped care for her younger siblings. She also engaged in various hobbies, such as writing and sketching the flora and fauna she encountered. Despite several suitors, Rita never married, valuing her independence and the freedom to pursue her interests over traditional domestic life. She became known in the community as an eccentric spinster, always ready with tales of supernatural occurrences and bizarre theories.

In 1805, at the age of 26, Rita moved into a small cottage on the outskirts of Hobart Town. She named it "Whispering Willows," a reflection of her love for the natural world and her belief in the mystical. Her cottage, located near the grand Jeffries Manor, became a sanctuary for her collections and a hub for her investigations into the unexplained.

Rita's life took a dramatic turn in 1821 when she claimed to have witnessed mysterious lights and heard peculiar noises coming from Jeffries Manor on the night of William Jeffries Sr.'s disappearance. Her account of extraterrestrial involvement was met with widespread ridicule and disbelief by the townspeople. However, Rita remained undeterred, growing increasingly obsessed with proving her theories.

She began to write extensive letters to local newspapers and authorities, detailing her observations and suspicions. Rita also amassed a large collection of artifacts and documents related to the disappearance, filling her cottage with strange objects and papers. Her relentless pursuit of the truth, however, took a toll on her mental health.

As the years passed, Rita's mental state deteriorated, and her obsession with the Jeffries case grew. Her family, concerned for her well-being and the safety of others, had her committed to the New Norfolk Asylum in 1842. There, she continued to insist on her theories, often speaking of the strange events she believed she had witnessed.

In her later years, Rita's behaviour became more erratic. She would frequently talk about being watched and claimed that the answers to the mysteries she pursued were close at hand. On November 9, 1844, at the age of 65, Rita vanished without a trace from her secure room in the asylum. Despite extensive searches, no sign of her was ever found. The official cause of her disappearance remains unknown, fuelling further speculation and mystery.