Taylor Swift's mom, Andrea, has been battling a brain tumor. The country-turned-pop megastar revealed the news in a new interview with Variety, ahead of the release of her new Netflix documentary, Taylor Swift: Miss Americana.

After Andrea was diagnosed with cancer in 2015, the disease returned in 2019, while the documentary was being filmed. "She was going through chemo, and that’s a hard enough thing for a person to go through," Swift explains. "While she was going through treatment, they found a brain tumor."

"And the symptoms of what a person goes through when they have a brain tumor is nothing like what we’ve ever been through with her cancer before," the singer adds. "So it’s just been a really hard time for us as a family.”

Swift has previously alluded to Andrea's health as a reason she's been sticking close to home as of late, performing only a few shows in support of her 2019 album Lover rather than touring intensely. The two are incredibly close -- "Everyone loves their mom; everyone’s got an important mom,” Swift tells Variety. "But for me, she’s really the guiding force" -- and Andrea, along with Swift's dad Scott, is well-known among Swift's fans.

"I wanted to be able to perform in places that I hadn’t performed in as much, and to do things I hadn’t done before ... But I also wanted to be able to work as much as I can handle right now, with everything that’s going on at home," Swift says. "I mean, we don’t know what is going to happen. We don’t know what treatment we’re going to choose."

Swift's Lover album includes a song about Andrea's cancer battle: "Soon You'll Get Better" is a stunningly personal track featuring the Dixie Chicks, one of Swift's favorite country groups.

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