The "Exorcist girl" is actually a young boy named Linda Blair, who was 13 years old when she starred in the 1973 film The Exorcist.
Linda Blair's performance as Regan MacNeil, the possessed young girl, was groundbreaking and helped to make The Exorcist one of the most iconic horror films of all time. She received an Academy Award nomination for Best Supporting Actress, becoming the youngest nominee in that category at the time.
It's important to note that while Linda Blair was 13 when filming The Exorcist, Regan MacNeil's age is never explicitly stated in the film. However, she is shown attending a Catholic school and is likely to be around 12 years old.
