Courtesy The Day Family

Patients at a children's hospital in Cincinnati will have a merrier Christmas this year thanks to a donation of 4,000 toys by one of their own, a 14-year-old undergoing brain surgery.

Savannah Day, of Troutsville, Va., and her two sisters, six-year-old Chloe and 17-year-old Sierra, collected the toys in less than three months after they found out in September that Savannah and their entire family would spend Christmas at Cincinnati Children's Hospital Medical Center.

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Savannah was diagnosed over the summer with Chiari malformation, an overgrowth of the skull that causes spinal fluid to build up in her brain. She underwent surgery today at the hospital to remove part of the overgrowth and drain the fluid from her brain.

"I think it was in the moment of them finding out that they would be in Ohio for Christmas that they wanted to bring Christmas to everybody else that was here," the sisters' mother, Michelle Day, told ABCNews.com today from the hospital.

"They looked at me and said, 'We're not going to have a Christmas so we want to take Christmas to everyone that's not going to have a Christmas like us,'" said Day, who was told by the hospital that there would be 500 patients at Christmas.

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"I told the girls, and they never flinched and said, 'We'll just ask more people, Mom,'" she said.

The Day sisters, all three cheerleaders, started a Facebook page - "Cheer 4 Savannah" - and spread the word through their respective cheerleading squads.

Soon the cheerleaders of opposing teams, local companies and even Little League teams were donating to the cause.

"Toys have just been coming to the house," Day said. "My husband's employer agreed to house them so we've just been sorting, labeling and boxing them."

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It quickly became clear that the girls would far exceed their original goal of 500 toys. By the time the family was ready to leave for Cincinnati, there were 4,000 toys in all and a local tractor-trailer company volunteered to drive the toys to the hospital.

Yesterday, Savannah and her sisters presented the toys to hospital officials. The toys will be distributed today to current hospital patients and one will be given to every new patient between now and Christmas. With the leftover toys, the hospital plans to re-stock its playrooms.

The Day girls' involvement in cheerleading led another sponsor, Varsity.com, to step forward and offer a way to keep the family's mission going. The cheer-focused company has created $5 "Cheer 4 Savannah" buttons that they plan to sell at cheerleading competitions and donate 100 percent of the profits to the "Cheer 4 Savannah" foundation the Day family plans to establish.

"That the girls are going to pay it forward after Savannah recovers, there's just not words for that," Day said. "The girls can keep buying toys to bring smiles to kids' faces."

If all goes well with Savannah's surgery today, her mom says she hopes to be back on the competitive cheerleading circuit in time for Nationals in the spring. By then, she'll also be ready to buy more toys for patients who will be going through what she's going through now.

"The girls are really ecstatic that their journey hasn't ended," Day said. "It's really just begun."

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