Moxxie Vixen is the daughter of Jack and Ela Vixen. She was born and raised in a strict, traditional Polish family. However, she had a very unusual upbringing, growing up without feeling the love and acceptance of her family. Moxxie's father was a Colonel in the Polish Army. He was a strong disciplinarian, and he raised her as though she were one of his men. Despite his harsh treatment of their daughter, Moxxie's mother never opposed her husband's methods. As a police officer, she believed in discipline and order, and that ultimately, her strict upbringing would prove beneficial. Moxxie's life was tough; her parents showed her little to no affection, and their degree of control over her made it almost impossible for her to maintain relationships with friends. The only activities she got to "enjoy" with her family, were training at shooting ranges and survival camps. However, they did allow her to work in the restaurant of one of her father's friends. It was hard work, but for her, it became a place of sanctuary from her parents. Her parents had always planned to send her to a military academy, but that was the last thing she wanted to do with her life. In a rare act of rebellion, she secretly tore up her application to the academy, and applied to medical school, instead. It was her dream to become a paramedic and pilot a medical helicopter.

Her only real friend was a girl named Zoe, who she knew from school. Zoe and her family were aware of Moxxie's home life, and her companionship and understanding helped to make life bearable. Unfortunately for Moxxie, Zoe's family moved to Los Santos. Zoe's family assured Moxxie that she was welcome to join them when she turned 18. When Moxxie's father discovered that she had hadn't applied to the academy, he was incensed. At the climax of a heated argument, he punched her square in the face, knocking her to the floor. Looking down at her, still ranting and raving, he screamed at her to get out. As far as he was concerned, he had no daughter. To him, she was nothing but a disappointment and a reminder of his failure. More out of desperation than expectation, Moxxie contacted Zoe in tears and explained her predicament. To her delight, Zoe's parents sent her a plane ticket and welcomed her into their home with open arms. This was the opportunity to begin the journey of her life that she had always dreamed of. This would be a new beginning for her, bringing renewed hope for the future, and an excitement for life and its many possibilities. Moxxie eventually landed at Los Santos Airport, with all of her belongings squeezed into a single suitcase, and the money she had saved from the restaurant in her account. After settling in, she enrolled in medical school and began her new life. She completed her studies with ease, graduating top of her class. Unfortunately, following her graduation, Zoe's parents went through a messy divorce, forcing Moxxie to find an apartment and support herself. Her direct and sometimes blunt approach to meeting new people paid dividends, and she has forged some strong relationships with people in the city. Although brought up in a strict environment, Moxxie does have something of a rebellious streak. As a teenager, she often stole food from the supermarket, or "borrowed" her neighbors' bikes. She occasionally feels socially awkward due to the way she was raised, and despite the fact that she learns quickly and adapts to her surroundings, she sometimes feels out of place in this very different culture. At heart, Moxxie is a sensitive and caring person, who does not need much to be happy. Although friendly and outgoing, she struggles to create lasting relationships with people who don't understand her quirky nature. She also tends to overthink things. Her lack of affection growing up has led to her struggling with attachment/abandonment issues. She is easily spooked and pulls away when things become "real", and can become attached to people too quickly, sometimes. This has resulted in several broken hearts, but she is brave enough to still love with an open heart and is fiercely loyal to those who return her love.

Having doubts and second-guessing her choice of career, Moxxie decided to take a break from the medical profession for the time being. Every now and then she is reminded of her upbringing and thinks of her parents back in Poland. Even after several years, she still hasn't heard from them and has no desire to make contact with them. Perhaps there can be a reconciliation of sorts, down the line, if only to allow her to put it all behind her, once and for all.