What is the name of a piano song with no lyrics, has a whistle sound, sounds like a waltz or lullaby?

I heard it playing at the Aveda Institute (Douglas J) in grand rapids michigan...i've heard it before but it seems like it could be from a movie...it has just piano (sounds like an old fashioned piano and not a fancy yamaha) and has a dreamy, whistle sound over it twards the end. There are no lyrics. It sounds like a lullaby, and the beat is waltz-y. it sounds like it could be from a movie. Sounds like Enya's piano songs and sounds like the song Avril 14th by Apex Twin...but it is not!! The melody goes something like: da da dum, da da dum, da da de de, da da da da...please help!!! slower song.