Piano (2001)

Uhk Gwan is a gangster but one day, he discovers he has a hidden 10 year old son named Jae Su. One day, he sees Hae Lim and falls in love with her at first sight. Hae Lim is a widow with two kids, 12 year old girl named Soo Ah and 10 year old son named Kyung Ho. She just moved to Pusan and opened a piano school. But somehow, her image gets destroyed and she finally accepts Uhk Gwan's love and the two marry. But shortly after, Hae Lim dies in a boat accident. Years later, all three kids are older and were raised by Uhk Gwan. Jae Su and Soo Ah are deeply in love with each other but they cannot express their love because they are family, although not by blood. Kyung Ho is a rebel and turns into a gangster too. The drama traces the struggles of these three kids and Uhk Gwan.