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Why Taylor's out to crush Billie

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JEALOUS Taylor Swift is launching an all-out attack on young rival Billie Eilish, whose new album is challenging Swift's grip on No. 1 in the sales charts, according to insiders who say the superstar intends to use the feud to crush the kid!

The 34-year-old Love Story singer unleashed her rabid fans on the 22-year-old to make sure Eilish doesn't outshine her, say spies, who claim Tay-Tay's furious at musicians who say she doesn't pen her tunes while praising Billie's songwriting.

"Taylor clearly feels threatened by Billie and the success she's enjoyed, and will do everything in her power to knock her down the charts," spills a source. "She uses her fans, so-called Swifties, to wage an online hate fest against Billie."