When she was seven years old, Ashley Peldon starred in the movie Child of Rage. Her role required that she scream a lot. This is when her ability to scream effectively and with variety was noticed.
Over the course of her career, Peldon has gradually developed a specialization: screaming. She adds screams to films and TV shows during the post-production phase to heighten the dramatic tension of the story. You may have heard her work in Free Guy, Paranomal Activity, and, appropriately, Scream.
Peldon has a lot more to offer than a Wilhelm Scream added into a soundtrack casually. She screams just the right scream for every occasion, as she explains in The Guardian:
As a scream artist you have to know the subtle differences between screams and determine whether they should peak at certain points, or remain steady for a very long time. I have to think: ‘OK, the character is scared here, but are they scared because their life is in danger or are they just startled?’ Those screams will sound very different. Ghost stories, for example, will often use a shrill, harsh scream because we need the audience to also experience fear.
-via Marginal Revolution