"As long as we're both here, we'll be best friends forever," said the bride, who bonded with the 10-year old over their similar journeys with cancer.
It's a special time in every little girl's life to be the flower girl at a wedding, but the walk down the aisle was all the more special for Abby Furco since, just a few months ago, she was told she had only 48 hours to live.
"Whether she was there or not, I wanted her to be my flower girl," said Sarah Rostock, 27, of Norfolk, Virginia.
Rostock told InsideEdition.com that she initially became involved with Camp Fantastic, a camp for kids with cancer, after she was diagnosed with biphenotypic leukemia when she was 14. After years of remission, the cancer returned when she was 20.
When she came back to the camp as a counselor, she met Abby Furco, 10, a camper at the time.
Abby, who is from Virginia Beach, Virginia, said she was diagnosed with leukemia when she was 4 years old. At 7 years old, her cancer returned.
Rostock said she reached out to Abby's mom when she heard the news of Abby's cancer, and asked if there was a good time for her to visit.
"That's one of the best parts about camp," Rostock said. "You really get to meet people who know what you're going through. That's why mine and Abby's relationship was so strong. It seemed like a lot of complications she had, I had as well."
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Abby explained they both got graft-versus-host as a result of their transplants. Even though she was declared cancer-free after transplant, her condition deteriorated in July, and doctors started discussing end of life options.
Immediately, Rostock left work to be by Abby's side at the hospital.
"Sometimes we have to give people reasons to make it," she said.
Rostock, who was engaged to her boyfriend of eight years at the time, decided to ask Abby to join her at the wedding as her flower girl, even though doctors at the time estimated she only had anywhere between 12 to 48 hours left.
"When I first asked her, we really didn't know if she was going to be there," Rostock said. "I probably just wouldn't have had a flower girl, I guess."
But despite the dire prognosis, Abby pulled through the first 48 hours. Then she made it back to summer camp weeks later. Next, she made it to her birthday.
Today, both Rostock and little Abby are cancer-free, thanks to the funding of St. Baldrick's Foundation.
So when Rostock's October 29 wedding day came, Abby was strong enough to walk down the aisle on her own.
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"She was my reality check right before we walked down," Rostock said, laughing as she recalled Abby's stoic response when she told her she was nervous about getting married. "When we walked back, we had a nice moment of just sobbing on each other. When you reflect on all that she's been through and all that life has thrown at us, it's an emotional time."
"I was just so happy for Sarah," Abby said, tearing up.
Rostock concluded, "As long as we're both here, we'll be best friends forever."
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