the name of a movie...help!

the name of a movie...help!
Perhaps someone could help me with something.On the plane last week travelling back from Shanghai to Zurich I saw a newish film but I can't find it anywhere on the Internet.It was about two boys in their teens to talk about a girl who plays piano and studies at a high school.By chance she comes to stay with her aunt near them in the same village for the whole of the summer.The two boys are both in love with her,but one of them wins the girl's heart.At the end of the summer she has to go home.The next summer,she appears to return,but in fact it is her twin sister (she in fact dies of tuberculosis).Do you know what the film is called,either in Putonghua or English?I want to buy it on DVD for my daughter.Thanks a lot!