In Desiderata Valley Tracy met Simon Fischer. A divorced man who lived with his son Elijah. She supported Simon in bad times and they got in love with each other. Simon and Tracy married soon and moved to the sea of Desiderata Valley.
In the new house Tracy started a job in the science career. She was interested in the supernatural beings and she wanted to research them. Tracy was a good-stepmother for Elijah but she wanted a child of her own. Tracy got pregnant and give a birth of a daughter Ellen. Simon and Tracy raised Elijah and Ellen to nice and well-mannered children. Tracy got in contact with Carla again and she told everything about Michelle, Simon's ex-wife. Thus she discovered that Carl, Elijah's best friend, was his half-brother. Tracy thought that Michelle was gone. So, she didn't know that her step-son visited his evil mother and that her husband cheated on her with Michelle. She also was surprised when Simon brought more passion in their relationship. It looked like Simon was younger...
After Michelle's death, the Sims of Desiderata Valley chased every supernatural being, every member of the Fischer family and everyone who dealt with Michelle away. They all moved to Fear Valley. In their new house, Tracy got pregnant again. A few days before Elijah moves to college, Tracy gave a birth to Evan. She saw Simon was upset after Elijah moved to college. So, she 'consoled' him. Between the birthdays of Ellen and Evan, Tracy discovered she was pregnant due 'the consolation'. Now she was home, she was seeing a rebel-version of her daughter. She went out late, she had a lot of boyfriends and Tracy worried about her. But finally she gave a birth to Eva. Now, she would concentrate on her career.
Tracy turned together with her husband in an elder. Ellen went to college and Evan and Eva were both children. Eva got sick, but nobody knew what kind of illness. Tracy researched this mysterious illnes and tried to make a medicine. Alas, it hadn't any effect and Eva died. Tracy pleaded to the Grim Reaper to rescue Eva. He said a lot of Sims in Fear Valley had cheated the death and he would finally take someone with him, but he agreed. However, the Grim Reaper will take revenge.
One night, her step-son Elijah visited her and he told about his 'problem'. He was turned in a werewolf and wanted some advice. Tracy told him the consequences and asked him a favor. She had been researching the supernaturals for years and she would like to be a supernatural creature too. So, Elijah turned her in a werewolf.
- Tracy's Dutch name is Tasja Visser.