Adele was born into the Starkweather family. As a child, she was well-loved by her family. At one point, she also befriended a faerie and called her "Hyacinth". Taking a page from their changeling practice, faeries and a young Axel Mortmain enacted their revenge on the York Institute for their crimes against Downworlders by switching Adele with the sickly child of a mundane family. She was since then raised by the family as Elizabeth Moore.
Elizabeth eventually married another mundane, Richard Gray, who was given a job by Axel Mortmain so he could get close to Elizabeth. When her apparent sister, Harriet Moore, bore a son, Elizabeth and Richard raised the child as their own to save Harriet the shame of having a child out of wedlock when her fiancé died.
Axel Mortmain, who knew of the role she would play in his plans, offered Richard a job to get close to her. Later, upon Mortmain's urging, she and Richard attended some meetings with the Pandemonium Club. She hated the meetings and wrote about them in her diary. At one point, Mortmain sent a Greater Demon, an Eidolon, to her, disguised as her husband to bear a child with her. Elizabeth then fell pregnant with their first child, Tessa Gray—unbeknownst to them to be a half-demon and half-Shadowhunter because of her heritage.
After Tessa was conceived, Mortmain gave Elizabeth the clockwork angel pendant, which Elizabeth accepted only because she realized that she would need it to ensure Tessa's protection and safe delivery. At one point, they finally and abruptly stopped going to the club meetings and left London with Harriet and Nate. The family moved to New York in secret, not wanting Mortmain to find out where they were headed.
When Tessa was three years old, she and Richard died in a carriage accident. Her sister, Harriet, then became the legal guardian of Tessa and Nate and has since raised them.
Years after her death, Nate found pages of her diary. To learn more about her past, Tessa also tried to Change into her using the clockwork angel that had once belonged to her, though she was never able to find even a trace of her essence in the object.
- Clockwork Angel (first mention)
- Clockwork Angel: Manga (mentioned only)
- Clockwork Prince (mentioned only)
- Clockwork Prince: Manga (mentioned only)
- Clockwork Princess (mentioned only)
- Clockwork Princess: Manga (mentioned only)
- The Wicked Ones (mentioned only)
- The Last Stand of the New York Institute (mentioned only)
- A rough estimate, based on her birth year, Tessa and Nate's ages and the fact that Tessa and Nate were three and six, respectively, when Elizabeth and Richard died. However, her age could range from 27 to 29, given that there were no specifics given to the time of their deaths.
- Clockwork Prince
- Clockwork Princess
- Clockwork Angel