McCardle was a student at GRACE Christian School in Raleigh.
According to Eric Bradley, GRACE Christian School's Head of School, Skyler was diagnosed with the flu last Friday.
Please join the @GraceEagles community in praying for Skyler. You can see her story on her caring bridge site. Last Friday, she was diagnosed with the flu. Today, she needs all the prayer and support we can offer. #PrayforSkyler https://t.co/ef1xH53DMu— Eric Bradley (@uganole) February 21, 2019
Bradley linked to Skyler's CaringBridge online health journal.
According to the blog, Skyler was in critical condition at Duke Medical Center following severe complications from the flu resulting in myocarditis - a rare inflammation of the heart muscle.
The blog also says Skyler had open heart surgery on Wednesday.
"She fought against this illness with everything she had, but alas it overwhelmed her body. Her bravery and strength will be something that we can all admire forever," the Caring Bridge blog said.
The school's website said Skyler was a cheerleader and the manager for the girl's volleyball team in the 2016-2017 school year.
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