Song on Episode Sleep

There is this most amazing song on the episode Sleep... its listed only as a " Bedtime Lyrics" on the credits... does anyone know any info on it? It's a beautiful song. Only has a few lyrics.. some of them are " Rest your heads..its time for bed... dream about counting sheep, dream about gazing stars..
that's all I can make out. If anyone has any info on it like who sings it or where I can get it - PLEASE let me know!



" If you can't say anything nice.. then come sit by me."