Liam Pádraic Aiken (born January 7, 1990) is an American actor. He has starred in films such as Stepmom (1998), Road to Perdition (2002), and Good Boy! (2003), and played Klaus Baudelaire in Lemony Snicket's A Series of Unfortunate Events (2004), based on the series of books.
Aiken was born in New York City, New York, the only child of an Irish-born mother, Moya Aiken, and Bill Aiken, an MTV producer. Bill died of cancer in October 1992, at age 34, when Liam was two years old. Aiken attended Dwight-Englewood School, graduating in 2008. He then went on to major in film at New York University.
Aiken made his professional acting debut in a Ford Motor Company commercial. He made his stage debut in the Broadway play A Doll's House at the age of seven, and his film debut in Henry Fool (1997). His first major film role came when he starred in Stepmom (1998). He appeared in Road to Perdition (2002) and the family film Good Boy! (2003). He turned down the role of Cole Sear in The Sixth Sense (1999) because his mother felt he was too young for the death-fixated role. He was also considered for the role of Harry Potter as he had previously worked with director Chris Columbus on Stepmom. However, as he is not British, Daniel Radcliffe took the part.