Taylor Swift has shared the sad news that her mother, Andrea Swift, is once again battling cancer. The country-turned-pop superstar offered fans the update in a recent piece she wrote for Elle magazine, entitled "30 Things I Learned Before Turning 30," a retrospective on the lessons she's learned leading up to her 30th birthday in December.

"I've had to learn to handle serious illness in my family," Swift writes. "Both of my parents have had cancer, and my mom is now fighting her battle with it again."

Swift adds that the experience has completely shifted her perspective on life: "It's taught me that there are real problems and then there's everything else," she goes on to say. "My mom's cancer is a real problem. I used to be so anxious about daily ups and downs. I give all of my worry, stress and prayers to real problems now."

Swift's mom was originally diagnosed with cancer in 2015. At the time, Swift explained that she had asked her mother to go to the doctor to get screened for health issues. Although "[t]here were no red flags, and she felt perfectly fine," they unfortunately received the news that she had cancer.

Swift has been relatively private about her mom's treatment and health updates since then, but wanted to make sure her fans were aware of the diagnosis. Andrea Swift has been one of the singer's closest confidants and friends along every step of her career, acting as cheerleader, road buddy and much more.

In her article for Elle, Swift addresses a variety of different lessons, including how her own experience with a sexual assault trial has taught her to believe victims who come forward.

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