Nielsen is an American author and literacy advocate. She writes fiction inspired by the world around her, history, and the power of imagination. Nielsen had many dreams growing up, one of which was to become a detective or spy. This is why characters like Hazel have traits like curiosity and problem-solving skills. Nielsen also considered being a teacher, and while her primary work is writing novels, she visits schools across the country to advocate for literacy. During these visits, Nielsen helps young audiences find their voice, discover the power of storytelling, and develop a love of reading. As of 2024, Nielsen has written 20 novels and coauthored several others. She writes both standalone novels and continuing series.

Nielsen uses the foundational story of the Titanic tragedy to illuminate a seldom-heard perspective on the experience of being on the infamous ship’s first voyage. She creates fictional characters and mixes them with known historical figures like Captain Edward Smith and Officer Murdoch to create a realistic historical fictional world. Hazel is 12 years old and has a sense of curiosity and boldness in doing what she wants rather than what others expect of her, traits common in people her age.