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Here's an interesting grouping that totally makes sense: Sean Ono Lennon, son of John and Yoko, has released a new song sung with Willow Smith, daughter of Will and Jada, and co-written with Carrie Fisher, daughter of Debbie Reynolds, long before her tragic death.

Listen to the piano-led, dreamy, quantifiably Beatles-esque (sorry Sean!) "Bird Song" below:

Lennon shared the following about "Bird Song" on Soundcloud:

"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."

Days after the December deaths of Carrie Fisher, age 60, and Debbie Reynolds, 84, Lennon shared many words of remembrance in a series of Instagram posts. One sample:

In January, he shared studio pics with Willow.

Next up, watch a super old-school Willow Smith interview: