The artist had namechecked their three children on the album, even using it to announce the name of their third daugther.
“I want to thank James, Inez and Betty and their parents who are the second and third people who I play every new song that I write," she shared.
Taylor publicly thanked Joe, surprising fans
Taylor had previously sampled the voice of their eldest, James, for Gorgeous, on the 2017 album Reputation.
Taylor also surprised fans by thanking her boyfriend Joe Alwyn, who responded by liking her Instagram post, hours after she publicly thanked the actor.
The pair have been dating since 2016 but have kept their five-year romance largely private.
Taylor and Blake has been friends since 2015
However, Taylor thanked Joe for being "the first person that I play every single song that I write," and revealed her memories of spending quarantine with him.
As the 31-year-old accepted her Grammys album of the year award, she said: "Joe, who is the first person that I play every single song that I write, and I had the best time writing songs with you in quarantine."
Joe later shared his support by "liking" her Instagram post
Joe wrote two songs on the 2020 album Folklore under the pseudonym William Bowery.
After the win, Taylor shared a picture on Instagram thanking fans.
"The fans are the reason we’re floating tonight, and we’ll never forget it," she shared, and Joe "liked" the post.
Joe and Taylor worked together on her 2020 albums Folklore and Evermore
Taylor won her third album of the year award on music's biggest night.
It was the only award the superstar won, and she accepted it with collaborators Jack Antonoff, Aaron Dessner, Laura Sisk, and Jon Low.
The Grammy win for album of the year also secured her a place in the record books as the first ever female artist to bag the award three years in a row.
Taylor is the only female artist to win album of the year three times
Billie Eilish took home record of the year for Everything I Wanted, Megan thee Stallion won best new artist, and H.E.R accepted the award for best song for I Can't Breathe.
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