(CNN) -- While the coastal town of Savannah, Georgia, fills with spectators on Saturday for the Rock 'n' Roll marathon, Chris Fenton and Laura Devrieze will be focused on the finish line.
For Fenton, crossing that line means completing his 10th marathon in six months. For Devrieze, it means finishing her first. For both, it's about running 26.2 miles for a parent with cancer.
Fenton and Devrieze are a part of the Leukemia & Lymphoma Society's Team in Training program. As the world's largest endurance sports training program, Team in Training has raised $1.2 billion for blood cancer research.
The program started 23 years ago when Bruce Cleland formed a group to run the New York City Marathon in honor of his daughter, a leukemia survivor.
Approximately 45,000 runners are signed up this year for the New York marathon, which takes place on November 6. Many are associated with one of the 200 registered charities; in 2010 the race raised more than $30 million for different causes.
Leukemia & Lymphoma Society communications manager Kristin Hoose says having a cause helps athletes focus on a goal, and having an athlete to support helps donors open their wallets.
"When people share their personal stories, and those of their heroes ... people see that their $10 can make a big difference."
A mother's strength
Chris Fenton was on a business trip in Kuala Lumpur, Malaysia, when he got a message from the secretary. His sister had called from Manhattan. Fenton looked at his watch and realized it was close to midnight in the States. Something was wrong.
"You hear those words for the first time: 'Mom has cancer.' You just kind of drop the phone and go into shock and say 'Oh my god. Oh my god. Oh my god,'" he said.
His mom, Barbara, is the matriarch of the Fenton family. As the second oldest of 14 children and a mother of six, Barbara received an outpouring of love after her non-Hodgkin lymphoma diagnosis. She had always taken care of everyone else, now they would take care of her.
Treatment was hard. Barbara endured four courses of chemo and four of radiation therapy. In October 2001, she went into remission.
Fenton's left Achilles tendon is screaming at him as he talks about his mom -- now the picture of health at 78 -- from home in Kohler, Wisconsin.
"She's settling in, loves to be a grandmother and spoil the grandkids, and (is) just kind of enjoying the golden years," he says with a laugh.
A long-time runner, Fenton started his journey to honor his mom in May. He's running 10 marathons (to celebrate her 10th anniversary of going into remission) in six months -- the time it took from diagnosis to remission. Since May, he has logged more than 200 official miles. Saturday marks his final race.
"I'm still a middle-of-the-pack plodder," he says, "but I'm able to find my way around a marathon course."
He has raised close to $100,000 over the last 10 years and hopes to continue supporting blood cancer research with Team in Training.
"My mom's story had a positive outcome. There are a lot of people who don't."
A father's joy
People loved Harry Devrieze. With thinning dark hair and bright blue eyes, he had a smile that lit up a room. Friends and family were his priority and he never hesitated to lend a helping hand.
The owner of a construction business, he often came by his daughter Laura's house in Carrollton, Georgia, to make repairs. It was from him that she learned plumbing, drywall and her way around the Home Depot store.
"He loved doing that -- he loved fixing things, he loved gardening, he loved working around the house."
Two years ago, Harry developed a rare, aggressive form of non-Hodgkin lymphoma. After chemotherapy, he was giving a clean bill of health, but the cancer returned and was discovered in January.
The Devrieze family was almost surprised by the intensity of the disease the second time around. The toll it took on Harry's body was more menacing.
"This was a full attack on his bones, his lungs, his muscles," Devrieze remembers.
It was during this time that she went to her first Team in Training meeting and signed up for the Rock 'n' Roll marathon. Running gave her time to clear her mind and be by herself. Her dad supported Devrieze's decision to race and to raise money for the Leukemia & Lymphoma Society.
"It was always important for him for me to be involved and kind of have a cause," Devrieze says. "He's the reason I was doing it, but he didn't want to be the reason I was doing it."
While she ran 5 miles, then 10, then 15, her dad started preparing for a stem cell transplant. He spent the month of May at Emory University Hospital. On Saturdays, Devrieze joined Team in Training in Atlanta for a run and then went to visit him.
Harry was released from the hospital in late June after the transplant didn't take. He passed away on August 16, 2011 at age 70.
For a couple of weeks, Devrieze refused to run, clutching to the friends and family Harry had held so close. Then she picked up her shoes and moved with the pain.
For Devrieze, Saturday will be yet another reminder of her loss. Her dad won't be there to watch her cross the finish line. That's why she's all the more determined to do exactly that.
"He was very proud and very excited. This is the longest I've ever run. It's mind over body, and having a greater purpose ... makes the mind part work better."