The evil and abusive Wendy Spector
Wendy Spector (Fernanda Andrade) was a villainess from "Asylum," the penultimate episode of Moon Knight (airdate April 27, 2022). She was the mother of the Spector brothers, Marc and Randall, the first brother being the series' main protagonist.
The episode revealed details of Marc Spector's childhood, which showed (in flashbacks) that when the brothers were children, they ran off and played in a cave as part of a reenactment from their favorite show, Tomb Buster. However, while playing, Randall ended up drowning in the cave, and his funeral showed his mother (among the relatives) mourning her youngest son's death.
Wendy was a loving mother toward both her sons, but after Randall's death, the woman turned heel and began abusive toward her eldest son Marc (beginning with blaming the child for his younger brother's death during his funeral). The villainess continued voicing her hatred, even refusing to celebrate his birthdays out of spite and anger. On Marc's 12th birthday, the evil Wendy continued her verbal abuse towards her son, accusing him of being jealous of Randall since his birth and claiming that she knew that Marc would cause his death.
A heartbroken Marc ran up to his room, and it was on that day that his dissociative identity disorder began as a coping mechanism against his mother's abuse (as he created the alter-ego known as Steven Grant). As for Wendy, she went up to her son's room and banged on the door and after entering, the maniacal villainess beat the boy with a belt out of anger.
The flashbacks revealed that Wendy's abuse continued for years until Marc moved out, with the evil woman also maintaining her hatred until her death.