Hey! My sister showed me an anime song, and it was so beautiful. I really want to watch it, but I have no idea what it's called.

It's about a boy who's a pianist. He stops playing because of his mom, but then he meets a girl. She plays the violin and inspired him to keep playing. Although, it's kind of boring to those who don't like classical music, it is just 'OH MY GOD. I'M CRYING' good.

Do any of you know it?