Hear Sean Lennon and Willow Smith Duet "Bird Song," Co-Written By The Late Carrie Fisher

In the wake of Carrie Fisher's death, Sean Lennon (son of Jon and Yoko) wrote a touching remembrance, professing his gratitude for the actress who he considered a lifelong friend.

Yesterday, Lennon shared a song co-written by Fisher, recorded in the weeks following her death with the assistance of Willow Smith (a "prodigal angel.") "Bird Song" bears a striking resemblance to The Beatles' "Because," swirled with harmonies and anchored by a bed of ivories; a heartfelt sonic salute. You can hear it down below along with a few word from Lennon.

"Carrie and I wrote this song years ago. When she died I just felt I had to record it. This is only a demo unmixed, we only had a few hours to record it. But the lyrics she wrote with me I think are marvelous. Carrie and I used to stay up til dawn chatting and pontificating about life. They were my best moments. Anyway... we wrote a song about staying up too late and hearing the birds sing. Willow Smith is a prodigal angel and was generous enough to lend her golden voice to this little tune."