Sarah is the emotional rock of the Monohan family, the mortar that keeps her clan together. She was born and raised on the south side of Chicago, and struggles at first to find her footing amongst the stately homes and tightly knit social circles comprising the upper-class community. Sarah's determined spirit and natural generosity help her to break through the toughest of exteriors, and she soon finds herself getting along with her new neighbors. Unbeknownst to her, some of them are guarding dark secrets which she is growing dangerously close to uncovering. She has developed friendships with Claire Radcliff and Karen Crezski, fellow members of the funraising council and seems to be a person of interest to Devon.
She is possessed by the ghost of Amanda Walcott the sister of the man that Nick kill and almost makes her kill her own family but its saved by Nick. After that he tells her the truth about the gates. (Surfacing)
Devon has been given her a strange tea that seens to be altering with her personality and eventually lets to her under Devon controls to poison Frank Buckley and indirectly to kill his wife Vanessa. This events make her and Nick decide to move out of the gates. (Bad Moon Rising)
She is easily one of the few people in The Gates that resemble the surroundings. She is beautiful, a loving and caring mother and woman who seems like a replica of the The Gates. She is a good friend, and she is also very likeable by the people that she lives with. Nonetheless, she can prove to be naive and manipulable by the people that wish her harm. In the fight between the vampires and the werewolves, she is shown to take the middle ground and tries to resolve their conflict. Despite that she is also a very strong woman that is not afraid to stand up and protect her family.