In the hallucination, Valentina was the daughter of Luke Graymark and Jocelyn Fairchild. She was named in honor of Jocelyn's first husband, Valentine Morgenstern, a hero in a war against Hodge Starkweather. The family resided in the Fairchild manor and were getting ready for Clary's wedding with Jace Herondale. Valentina had just disfigured their wedding cake and was caught by her brother, Jonathan, who was never touched by evil in the dream.
The illusion of the family Clary had always wanted was soon shattered, however, when Clary found out that Simon was never a part of her life in the false reality, since the demon maintaining the illusion was incapable of creating perfect illusions. This caused Clary to wake from the hallucination, wiping away the illusion.
Valentina was described as an adorable little girl of around four or five years of age, with red hair the same shade as Clary's, and blue eyes, exactly the same as Luke's. In the illusion, her face had been smothered in chocolate, and she was wearing a green lace dress to Clary's illusory wedding.
- Ironically, Jonathan teasingly called her "demon child" in the illusion.