Mary Shelley lived in the betrayal of her parents, haunted by her mother's abandonment and the incompetence of her father and his wicked stepmother. Her stepmother was quite actively jealous of her predecessor's daughter and resented the bond between father and daughter. After his remarriage, Mary resided in her own silence, reading by her mother's grave.
Wollstonecraft, Mary's mother, died of puerperal fever eleven days after the August 30, 1797, birth of their daughter, so that Godwin was left with the infant and a step-daughter, three year old Fanny. In marrying Mrs. Clairmont, Godwin hoped to find at last the helpmate he sorely needed to supply the children with a mother's guidance. However, his young daughter's insecure bonding to him already set by her being used to the strictly only father daughter relationship, the disruptive transition to a refashioned household with a new wife and her partiality for her own children, Godwin's remarriage instead "helped activate in Mary a lifelong desire to compensate her father for the loss of his exquisite first wife and their short- lived marital happiness".
The theme of parenting throughout Frankenstein, reflects Mary's own tragedies with childbirth and upbringing. She lost her own child and tried desperately to recreate life with in and she was abandoned by her mother in death and left with a father who held an interesting relationship with his daughter. Mary only had one child to reach adulthood and one nearly killed her during a miscarriage. Although, only one child had been born and died by her nineteenth year, childbirth, pregnancy and parenting were very important issues in her life at that time, thus being described in Frankenstein.
You can easily imagine Mary Godwin, in part, angry with a father who did not in return recognize her anger...