Allison is one of the seven children that Sir Reginald Hargreeves adopted in order to form the Umbrella Academy. She and her siblings–Luther, Diego, Klaus, Five, Ben, and Vanya–possess unique superpowers, giving Reginald the chance to form a crime-fighting team. Unlike Vanya who was forced to sit on the sidelines, Allison fought on the frontlines with her "I have a rumor" ability. By prefacing with those four words, Allison can influence events with mental manipulation. In addition, her powers allow her to technically get anything she wants in life. Whether it's distracting villains or preventing cops from beating her husband, Allison has showcased her rumor power. She has also used it on her family whether it was convincing Vanya to forget her own power or to force Diego to punch himself in the face.
Despite possessing the rumor ability, Allison learned on multiple occasions that it's easy to abuse the powers. Prior to Reginald's death, Allison was living her husband, Patrick, and young daughter, Claire. One night, Allison was sharing stories of the Umbrella Academy before putting Claire to bed. After the young girl refused to go to sleep, Allison used the rumor power to make her daughter tired. Patrick witnessed the manipulation, leading to their eventual divorce. As part of the separation, Patrick received full custody of Claire. There was a presumption that Patrick was fully aware of Allison's abilities, but she vowed not to use them on her family. After losing her daughter, Allison viewed her powers more of a curse than a gift.