Lilly Bainbridge is a pivotal character on the HBO show IT: Welcome to Derry. The series is a horror story set in the town of Derry in 1962, featuring the famous character named Pennywise. The young actress who portrays Lilly on screen is Clara Stack.Lilly's role is that of a 12 to 13-year-old girl who grapples with an immense sense of guilt and sorrow. She blames herself for the death of her father in a terrible disaster that occurred in a pickle-jarring factory. Lilly is affected by schoolmates bullying her, and the children make the meanest jokes about her father and his sad demise.IT: Welcome to Derry explains how Pennywise uses Lilly's grief and fear to punish her even more. Clara Stack herself is 15 years old in real life, as per a report published by Deadline on November 04, 2025. Her performance shows how Lilly tries to survive the monster's attacks while carrying the pain of her past.What is Clara Stack's real age? View this post on Instagram Instagram PostBorn on October 19, 2010, Clara Stack is 15 years old. She began performing in local plays when she was only four years old. Clara has also appeared in several popular TV series, including Madam Secretary, Bull, and Almost Family.She also portrays an uncouth incarnation of the role of Hailee Steinfeld in the Marvel television series Hawkeye, available on Disney+. She co-starred in Naughty Nine, a 2023 Disney film, as Rose. Clara lives in New York and has a twin sister, Maggie. Her role as Lilly in IT: Welcome to Derry is her biggest role yet.How old is Lily in the HBO series? View this post on Instagram Instagram PostLilly Bainbridge appears in IT: Welcome to Derry as a little girl of around 12 or 13 in 1962. The series gives clues about her age through dialogue and newspaper clippings. Matty Clements is 12, and his closest friend is Lilly. This fact makes the viewers realize that Lily is about 12 years old when the series begins.She is enrolled in Derry High School, which has students from the 6th grade up to the 12th grade. The character is three years younger than Clara Stack. Still, her performance in IT: Welcome to Derry feels real and helps young viewers connect with Lilly as she faces the terror of Pennywise.Why is Lilly's age important to her story? View this post on Instagram Instagram PostIn IT: Welcome to Derry, Lilly Bainbridge is 12/13 years old. Her father died in an accident at the factory, and she already has to cope with his death. She has been guided by this memory and has been full of guilt, as the tragedy happened when she asked him to go back into the factory to get her mood ring.She is bothered by bullies at school because they take advantage of her by cracking mean pickle jar jokes on her. Pennywise reads her vulnerability and exploits it to haunt her with frightening dreams. The fact that Lilly is young reveals that children are easy targets of such evil.Follow Soap Central for more updates!