By Lisa Hughes

HOLLISTON (CBS) – To spend time with Declan Vail is to experience an elevating joy. Whether he is plucking a guitar in his playroom, putting on a puppet show with his younger brother Teagan or riding in the back of a police car to the Dana Farber Jimmy Fund Clinic, he is the embodiment of happiness. And yet, this bubbly, outgoing three year-old is fighting a brain tumor. An inoperable brain tumor that has thrown his family’s life into–some degree of–chaos and uncertainty. “I think he has always been brave and strong but he is steadfast in it now,” his father, Jeremy told WBZ’s Lisa Hughes. “He has been tremendous.”

Declan started having seizures in May. At first, they came for just ten seconds every other day. But by the time a nurse was able to capture one of the seizures on an EEG machine, he was having the episodes more than five times a day. A day after he began treatment for epilepsy, test results revealed that the real problem was a brain tumor.

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Stephanie and Jeremy Vail were in shock. “I think we are still in shock,” Stephanie said. “It’s only been four months and we haven’t had two minutes to really process anything. You get a diagnosis…you hit the ground running. You are doing everything you can to find out what’s going on.”

Declan, Jeremy and Stephanie (WBZ-TV)

Jeremy’s sister arrived at the hospital within the hour and began taking notes, asking questions and sparing the couple from trying to retain information they could not begin to process. Initially, they felt frightened and alone. But as soon as friends and colleagues learned about Declan’s diagnosis, a flood of support rushed in to buoy them.

One friend set up a meal train. Another insisted that the Vails let her set up a GoFundMe page. Co-workers stepped up with generosity. Stephanie is a nurse who treats spinal cord and brain injury patients at Spaulding Rehabilitation Hospital in Cambridge. She says her boss called her every day and soon after sharing news of Declan’s diagnosis with the staff, Stephanie’s colleagues surprised her with an incredible gift. They pooled 304 hours of “earned time” and gave it to Stephanie so that she could spend three months caring for Declan without losing her paycheck. The Vails say it meant everything. “At first, you’re thinking… what can I sell? What can I offload? What bill can we get rid of? To have the support of her workplace—you’re covered for your three months off…it was massive.”

Declan Vail (WBZ-TV)

Then, Jeremy’s karma kicked in. As a bike mechanic at Landry’s in Natick, he had helped Pan Mass Challenge riders who raise money for cancer care and research at Dana Farber Cancer Institute. For ten years, he’d worked the August event. Now, suddenly, many of the riders wanted to help his family. Two people who helped spread the word about the Vails’ GoFundMe page were Steve and Ellen Branfman. Longtime PMC riders, they know the pain of losing a child to cancer. After their son Jared died of a brain tumor, they founded the PMC’s Team Kermit.

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When the Branfmans learned about Declan’s condition, they reached out to the Vails, promoted the GoFundMe page within the cycling community and asked the PMC if Declan could become their second Pedal Partner. (By incredible coincidence, their first Pedal Partner is also named Declan.) PMC weekend, the Vails were on the course cheering on riders who drew inspiration from Declan. “I told a lot of them, Jeremy says smiling, ‘when the hills are steep, think of his smiling face and you’ll get to the top.’”

Declan Vail (WBZ-TV)

The day of Declan’s first MRI since he began monthly chemotherapy treatments, it was a PMC rider who picked him up for a ride to the hospital. Officer Ryan Haney wasn’t wearing cycling clothes. He was dressed in the uniform of his profession. Haney is a Bentley University police officer. After meeting the family at the PMC, he volunteered to take Declan to Boston Children’s Hospital and to wait with the family—all day—to drive them home from Dana Farber.

“Declan’s great. The family’s amazing. The kid’s got—probably—the brightest outlook on life, you know. Lot of stuff going on in the world and the kid still wakes up with a smile.”

Web Extra: Jeremy and Stephanie on Declan’s diagnosis

Getting in the back of the cruiser, Declan—wearing a police uniform of his own—was beaming. His entire face lit up with the excitement of a boy about to experience an adventure of his dreams. Later, Jeremy will admit that leading up to the appointment, he had “scan anxiety” but tries not to project his fears on Declan.

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He says they try to follow Declan’s lead. “He’s showing us how to do it.” Stephanie agrees. Her three year-old is wise beyond his years. “Don’t be blinded by a diagnosis. It can bring positive things into your life, not that I wish this upon anyone…But if I were going to do this again, I would want this community and this set of people that are helping us. They have made a huge difference in our lives.”

Lisa Hughes