 -- Throwing a surprise “Sweet 16” party in the age of cellphones and social media is no easy task. But an entire Virginia community pulled it off for a girl with cancer.

The night of her birthday, Abby Snider thought she was going to give a speech to help raise money for the Stillbrave Childhood Cancer Foundation, a local charity that provides non-medical support for the families of kids with cancer. It was all part of an elaborate ruse to bring the teen to the George Washington Hotel in Winchester, Virginia, last Thursday evening, where 100 people (including a team from ABC affiliate WJLA) were waiting.

Snider, who was diagnosed with leukemia a year ago, spent weeks writing her speech. At the same time a group of friends, family and complete strangers worked quietly behind her back to plan the big bash. AES, a local car service, provided a stretch limo. SAS salon arranged for makeup. Other vendors donated food, flowers, photography and entertainment.

Snider’s parents had wanted to throw her the fancy sweet 16 she has been dreaming about since she was 2, she said, but with the mounting medical bills it just wasn’t in their budget. Tom Mitchell, who runs StillBrave, stepped in to rally local businesses.

“It was amazing to see how many people in community embraced the idea and helped to pull it all together,” he said.

Snider was expecting a car to pick her up for the fundraiser, so she said she was pleased rather than suspicious when a stretch limo pulled up to her house. She thought the makeup session was simply a nice touch too. None of this tipped her off to the party.

But when she walked into the ballroom and everyone shouted, “Surprise,” Snider told ABC News she was blown away.

“At first I was confused and then I started screaming and then I started crying," she said. “It was awesome. I literally felt like Cinderella for the night.”

Snider said the chemo used to treat her disease has brought her to the brink of death several times. Just recently she spent three weeks in the hospital with acute pancreatitis that resulted from her latest treatment.

“There are times you just want to give up but you have to keep going,” she said. “Even when it’s hard you just have to keep fighting.”

After missing last year’s birthday because she was too ill, Snider said she’d hoped for some kind of party this year, even if it was something small. Mitchell told ABC News he was relieved that all involved managed to keep it a secret.

“I hated lying to her but she definitely bought it hook, line and sinker,” he said.

Mitchell said the only downside to the ruse was that Snider worked so hard on a speech she didn’t get to deliver. But Snider said she’s good with that.

“I was freaking out about it and I was so relieved I didn’t have to give it,” she said. “I’ll save it for another time.”