Taylor Swift and her mother Andrea Finlay Taylor Swift and her mother Andrea Finlay

Taylor Swift's mother, Andrea Finlay, has been diagnosed with cancer.

Swift revealed the news Thursday in a Tumblr post to fans titled "Just So You Know."

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"Hey guys," she writes. "I'm writing to you with an update I wish I wasn't giving you, but it's important and I'm used to sharing important events in my life with you."

At the end of last year, the 25-year-old singer explains, she asked her mother to go get a health screening as a Christmas present for her. "She agreed, and went in to get checked," Swift writes. "There were no red flags and she felt perfectly fine, but she did it just to get me and my brother off her case about it. The results came in, and I'm saddened to tell you that my mom has been diagnosed with cancer."

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Swift and her family are keeping details of her mother's condition, and her treatment plan, private.

She ends the post by explaining why her mother wanted her to share the news: "Your parents may be too busy juggling everything they've got going on to go to the doctor, and maybe you reminding them to go get checked for cancer could possibly lead to an early diagnosis and an easier battle. ... I hope and pray that you never get news like this."

Read Swift's full post here.