Mathilde Prudence Goth is the first daughter born to Cornelia and Guther Goth in 1964. She is the second child to her parents, after Mortimer and the older sister of Marjorie MacDuff and the late Gunther Goth Jr. She was born the same year as her maternal cousin Katheryn Landgraab, whom was also raised by Cornelia along with her sister, Mary-Allison Darling. Like her mother, she is a witch, she often struggles with spells and rules, especially in the shadow of her cousin Katheryn Landgraab who is exceptionally well in this category, but not as naturally talented as Mathilde.
Mathilde is kind-hearted in nature and often strived for her mother's affection growing, ironically Marjorie often envied Mathilde as children because she believed that their parents favored Mathilde. Mathilde's thirst for attention could have possibly led to why she consistently stuck out past curfew to see Toby Gunn, despite her parents disapproval of their relationship. Shortly after graduation, Mathilde became pregnant with Toby's baby. Enraged, Cornelia kicked her out, further straining their relationship. Gunther agreed to stay neutral and often paid Mathilde's bills, as (like Marjorie has said) he favors her over his other children. Toby Gunn is flirty and promiscious, he was a romantic interest of Mathilde's and was often unfaithful. He refused to move in with her to help with their daughter, Jessie, subsequently leading to her disliking him. She is good friends with her daughter who had no relationship with her father Toby. Katheryn Landgraab is her best friend and basically her sole supporter through her pregnancy with Jessie, leading Mathilde to name her daughter after her cousin. However, Mathilde does not get along with Katheryn's sister, Mary-Allison Darling. She is only friends with her brother Mortimer. It is suggested that part of her surprisingly rebellious behaviour is a result of her brother Gunther's sudden death.