BOSTON (CBS) - One man runs with his daughter, while the other runs for the daughter who is no longer with him.
They are Greg Kelly and Glen Jusczyk, and together they are running the 116th Boston Marathon in the hope that someday, no other father will know their pain.
Related: Boston Marathon Guide
Charlotte Kelly was just two-and-a-half when she became ill in 2009 with Neuroblastoma, a cancer of the nervous system most common in young children.
"She had a very large mass in her belly; an abdominal tumor," said Kelly, who will be running his second Boston Marathon on April 16. "She was already at stage-four at the time it was found. She fought for close to three years."
Charlotte lost her fight this past winter.
The Jusczyks are fighting a similar fight right now.
"She's been through a lot," Glen Jusczyk said of his three-year-old daughter Malia. "She's a tough kid. Her, Charlotte; all that have to deal with it."
Originally from Massachusetts, the Jusczyk's were living in Orlando when Malia became ill a year ago. The diagnosis was Neuroblastoma.
"Four white coats showed up and we knew at that point," recalled Jusczyk. "We just started scrambling."
So the they came home to Boston, to their families and to Dana Farber. And, by chance, the Kellys --whom they had never met -- were waiting for them.
"My dad went on this Neuroblastoma blog: N-Blast," said Jusczyk.
"I read this message out of pure luck, and just responded to the message," recalled Kelly. "The next day I was in Dana Farber with Charlotte, and I walked into the room and saw two people."
"He said 'are you from Florida?'" remembers Jusczyk.
"They had a look to them that I imagined that's what I looked like in the beginning," said Kelly.
"We were in beds next to each other; Charlotte having her blood count tests, Malia in chemotherapy. It's a small world," Jusczyk recalls.
While Charlotte is gone, the bond between the two fathers is strong. Greg ran for the Dana Farber team two years ago, and this year, he and Glen will go the distance together. It will be Glen's first official Boston Marathon, although he has conquered 11 Iron Man competitions.
"It's a good week to escape," said Kelly. "It means more when you're out running and I think about Charlotte. It's nice."
And if you're our on the course on race day, you shouldn't have too much trouble spotting these two.
"I haven't shaved since Charlotte passed. It's my Neuroblastoma tribute," Kelly said, stroking his beard. "Malia's favorite color is pink, so I think I'll dye it pink for the race."
"You'll spot me."
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