The Wonder Years.

A 13 year old girl who lives with her widowed mother in a town in Korea. Somewhat withdrawn and living in dreams, her main dream is that her real mother is a famous pop singer. Soo-ah falls in with a delinquent schoolgirl, and after a tense argument with her mother, blurts out that she is not her real mother. She runs away on a train to Seoul to see her "real mother" at a concert and be with her.