Taylor Swift and her mother, Andrea Finlay, on Dec. 22 in New York. (NCP/Star Max/GC Images)

Taylor Swift asked for an unusual Christmas present last year: She wanted her mother, Andrea Finlay, to go to a doctor to "get screened for any health issues." On Thursday, Swift said that the results of those screenings came back, and that her mom "has been diagnosed with cancer."

Swift's announcement, posted to Tumblr and tweeted from her official account, indicates that the music industry's best-selling star intends to keep the details of her mom's exact diagnosis and condition private.

But her mother wanted her daughter to talk publicly about part of the story, for one very good reason, Swift wrote:

She wanted you to know because 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… Or peace of mind in knowing that they’re healthy and there’s nothing to worry about. She wanted you to know why she may not be at as many shows this tour. She’s got an important battle to fight.

Thank you for caring about my family so much that she would want me to share this information with you.

I hope and pray that you never get news like this.

The full post is here.

Shortly after the singer made her mother's diagnosis public, #prayformamaswift began trending on Twitter.

[This post has been updated.]

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