BOSTON (CBS) - A mother–daughter duo is running as a way to say 'thank you' to Boston Children's Hospital.
Mary Higgins and her daughter Meghan Dunne will be side-by-side as they head out on the trek from Hopkinton to Boston.
Mary is a Boston Marathon veteran.
"This is my eighth Boston," says Mary. "And it never gets easier."
For Meghan, it will be her first.
"I've always wanted to do it," Meghan told us, sitting at the Phillips Academy track where she's finishing up her post-graduate year. "My siblings did it with her, and I kind of wanted to fit in."
Both will be running as part of the Boston Children's Hospital team. Mary's youngest son, Ryan, was diagnosed with a serious heart problem and, at 3 years old, had to have surgery to fix it.
"At birth, he was diagnosed with a bicuspid aortic valve at Children's and then he had blockage stenosis," says Mary. "So, when he was 3, it was very successful. And he has been monitored ever since, and now, he is a healthy, hockey-playing, track-running 15-year-old. And I want to pay it back to Children's for all the care that they have given us."
Meghan says Ryan has always been there for her. "He's my bestie. He's a couple years younger than me, and we've kind of been through a lot together. So, when I'm running, I think of him. And I thank Children's for giving me my best friend."
And Ryan won't be the only one in their hearts along the way.
Mary and Meghan lost Casey, a daughter and sister, at the age of 16. Blood vessels burst in her brain leading to her death.
"We'll have a few angels watching over us, for sure," says Mary emotionally. "We have a special girl up there."
"We're holding Ryan with us," Meghan adds. "We're holding Casey with us, too."
And on the course, they will have each other. Bonding over 26.2 miles.
"It's really, really awesome to run with my kids and see that I'm sharing a passion of mine with them."
Meghan wants her mom to know this has meant the world to her. "I would not be able to do it alone. Because she has told me everything from, like, putting Vaseline in your toes, which is like really weird but..."
"It works!" Mary chimes in with a laugh.
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