From Aniboom : An old man shares his life story on the piano with his young grandchild through evocative music.

The song is: "Comptine d'un autre été: l'après midi" composed by: Yann Tiersen, a sortof minimalist (mostly piano) composer like Philip Glass.
Animation by Aidan Gibbons.

That is very beautiful. A very moving piece.

Thanks for posting that.  It was a great way to start the weekend.