Family and close friends had been sharing frequent updates on Gabriella's condition in recent days at the "Make a Wish with Gabriella" Facebook page and made the announcement on the page Sunday:
"It is with the heaviest of hearts and the greatest of love that we share the news that our daughter Gabriella passed away last night. Details of a memorial service are forthcoming. Thank you for loving our daughter and for all of your support."
Gabriella was diagnosed with the walnut-sized tumor in 2012 and launched a Make-a-Wish campaign, along with other fundraising and awareness programs focused on childhood cancer, including the Smashing Walnuts Foundation.
The Washington Post points out that Gabriella raised more than $275,000 for the Make-a-Wish foundation in a letter-writing campaign last year.
"She submitted her own request — for a dream trip to Paris, which she took with her family in May — soon after she was diagnosed in November 2012," according to the Post. "But the philanthropic student also wanted to make sure that other children would have their wishes granted, her mother, Ellyn Miller, said at the time."Read more of the Washington Post report.
Earlier this month, Gabriella received her honorary degree from Shenandoah University.
“You all know that I have cancer and I’m going through some challenges,” she said during the graduation ceremony. “What gets me up every day, especially on the weekdays, because I’m not a morning person, is that I love to go to school and learn.”
Read: Leesburg's Gabriella Miller, 10, Receives Her College Degree
The Washington Post also noted Gabriella's comments when honored as the Loudoun County Volunteer of the Year in May. She said, “You might have a bad day today, but there’s always a bright star to look forward to tomorrow."
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