Jocelyn is Clary's mother and known as Jocelyn Fairchild as her maiden name and Jocelyn Morgenstern as she married to Valentine Morgenstern. She is a great Shadowhunter at her time and join The Circle with his husband and friends. After the Uprising brought by Valentine, she make herself a fugitive and runaway from Valentine and Shadow world. She takes the Mortal Cup with her and hides it. When she escaped she had Clary in her womb.

Jocelyn wants to protect Clary by wiping out Clary's memory with Magnus Bane's help. She never tells her daughter about Shadowhunters. She lives with Clary and Luke just like a normal family until Valentine's underlings comes to search the cup. Jocelyn drinks a potion that puts her in coma. Until the end of the story she has not woken up.