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Shortly before his fairytale date with Taylor Swift, cancer-stricken teen Kevin McGuire was hospitalized and will no longer be able to attend the ACMs tonight.

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On Saturday Swift posted a message to her Twitter page sharing the sad news.

"Just talked to Kevin McGuire," she wrote. "He's not well enough to join me at the ACMs. Please keep him in your thoughts. I'll make it up to you, Kevin!"

Taylor asked the 18-year-old to the ceremony after his sister started a campaign to get her to attend his prom. Swift was unable to attend the event, but offered the ACM date instead.

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It's not clear why McGuire has been hospitalized, but a Facebook posting on the teen's behalf writes:

"I am so sorry to announce this devastating news, but Kevin was admitted to the hospital last night, and is unable to attend the Academy of Country Music Awards with Taylor Swift. As we should all live by the motto 'live for today' a cancer patient feels the impact of these words far too hard. We appreciate everything you have done for us, and we know you are all hurt from this too. Please continue to pray for Kevin and his health, because that is the most important thing. As for Taylor, she is just as depressed as all of us to miss out on this date, and we are so thankful for the opportunity she has given us."