Your lie in April

Kōsei Arima was a piano prodigy until his mother died when he was eleven years old. The shock of losing her made him lose any interest in piano, and his life has felt monotonous ever since. Then, when he's fourteen, his childhood friend Tsubaki introduces him to her classmate Kaori, a free-spirited violinist. Her enthusiasm reignites his interest in music and in life.

Synopsis from Anime News Network