Mother Cecilia first appears in the series premiere, where she is shown to be the head of the nuns in the priery and on friendly terms with the priery head Prior Anthony. She is also friends with Caris and encourages her pursuit of medicine. She also comforts Caris in the aftermath of Mattie Wise's wrongful execution, saying that she admired Caris for standing up for Mattie and wishing that she had had the courage to do the same. Though Mother Cecilia attempts to fund Caris' attempts to build a hospital, Godwyn sabotages the pair's efforts. Later, when Caris is accused of witchcraft, Mother Cecilia is able to save her life by convincing her to become a nun. Tragically, Mother Ceclia later becomes one of the many victims of the Black Plague.