"Bird Song" features vocals from Willow Smith
Sean Lennon and Carrie Fisher
Credit: Cindy Ord/Getty Images; Dimitrios Kambouris/Getty Images

Sean Lennon released a new song on his Soundcloud page Monday. Featuring Willow Smith on vocals, “Bird Song” is a quiet and lovely tune about staying up too late and hearing dawn sounds begin. But in the description, Lennon added another melancholic note with the revelation the song was co-written by the late Carrie Fisher.

“Carrie and I wrote this song years ago,” Lennon wrote in his post. “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.”

Listen to “Bird Song” below.

After Fisher’s death, Lennon remembered her as “one of the best and closest friends I’ve ever had in my life.” He shared many photos of them together and in one caption he wrote, “To Carrie, I hope you and David and George Martin and Prince and Leonard and the others lost this year are having the best party ever, and I hope my dad greeted you at the door.”