She has been battling cancer for some time.

Taylor Swift recently revealed that her mother, Andrea, has been diagnosed with a brain tumour. The 'Look What You Made Me Do' singer has spoken briefly a few times about her mother's illness, this week stating that her health has deteriorated somewhat. "The symptoms of what a person goes through when they have a brain tumour is nothing like what we've ever been through with her cancer before," she told Variety. "So it's just been a really hard time for us as a family." Swift had spoken briefly about her mother's cancer prior to this, when she wrote a piece for Elle magazine about growth and perspective. "Both of my parents have had cancer, and my mom is now fighting her battle with it again," she wrote at the time. "It's taught me that there are real problems and then there's everything else. My mom's cancer is a real problem." The singer's Variety cover shoot comes ahead of her upcoming Netflix documentary, Miss Americana.  The film will provide a never-before-seen glimpse at Swift's life, her work, and her fight to reclaim her music during a legal battle with Scooter Braun. The synopsis reads: "Miss Americana is a raw and emotionally revealing look at one of the most iconic artists of our time during a transformational period in her life as she learns to embrace her role not only as a songwriter and performer, but as a woman harnessing the full power of her voice." Swift said that while she was filming the movie, her mother got sick for a second time. “Everyone loves their mom; everyone’s got an important mom,” she continued. “But for me, she’s really the guiding force. Almost every decision I make, I talk to her about it first. So obviously it was a really big deal to ever speak about her illness. “She was going through chemo, and that’s a hard enough thing for a person to go through." Miss Americana will be streaming on Netflix from January 31.