When Marlborough resident John Tanner, 47, was preparing to run a marathon, he often got a phone call from his young friend Nicholas Dainiak.
“Go John,” Nicholas would say, according to his grandmother, Dorothy Noyes. “My hero.”
That was back when 9-year-old Nicholas could still speak, before a degenerative condition called Batten disease took his voice, along with his vision and his mobility.
“He could just form the words,” Noyes said.
For four years, Tanner used every road race he ran to raise awareness of his young friend’s condition and collect money for the Our Promise to Nicholas Foundation, which helps fund Batten disease research. It was during one of these races, the New York City half marathon, that Tanner suffered a fatal heart attack on March 17.
“He was a very kind, very generous person,” said Tanner’s twin brother, James, of Framingham. “His presence touched a lot of people’s hearts.”
John Tanner leaves his mother, Evelyn Tanner, four siblings, longtime girlfriend Kim Hilner, a sprawling extended family, and many friends and colleagues.
At the time of his death, Tanner was training for this year’s Boston Marathon, which he planned to run, as usual, for Nicholas. In Tanner’s honor, his friends are trying to raise at least $2,500 for the foundation.
“He was known for his kind and generous nature,” said Iris Belmore, a co-worker at Russell’s Garden Center in Wayland, where John Tanner worked in operations and his twin still works. “We are hoping to honor his legacy of giving,” she said.
Friends and family say Tanner was hard-working, unfailingly positive, and genuinely interested in the people around him. Losing such a friend and colleague was “devastating,” said Jack Russell, a retail manager at the garden center.
“The fact that it was so sudden made it such a shocker,” he said.
Tanner first became involved with Nicholas, who lives with his parents in Bedford, N.H., and his foundation shortly after the boy was diagnosed at age 5.
Batten disease is a rare genetic condition, striking roughly three out of 100,000 children, according to the Batten Disease Support and Research Association. It is a degenerative disease that causes seizures, loss of vision and motor skills, and mental impairment. Though drugs may help control some of the symptoms, there are no treatments for the disease; it is always fatal.
When Nicholas was diagnosed and his family discovered the lack of options, they threw themselves into raising funds for research, said his father, Chris Dainiak. One day, Noyes, who also works at Russell’s, was discussing these efforts with a co-worker. It would be great, she remarked, if someone who ran marathons could help publicize the cause and raise money.
Tanner happened to be walking past, overheard the conversation, and immediately volunteered, Noyes said. He had been running seriously for more than a decade, racing in at least three marathons a year, said James Tanner, who traveled with his twin to places like Germany and Ireland to cheer him on.
When John Tanner agreed to join the cause, he had a blue T-shirt made with the words Nicholas Research Fund — the foundation’s original name — printed across the chest.
After the first marathon Tanner ran in support of Nicholas, his co-workers at Russell’s took up a collection for the foundation, Noyes said. They poured the donations onto a table to count the money, and tallied up about $1,000, she said.
“He was really taken aback by how much people had donated,” she said.
From that point on Tanner sported his Nicholas T-shirt at every race; he was wearing it last month as he ran the first 12 miles of the half marathon in New York.
Over the years, Nicholas and Tanner became friends, Dainiak said. They would see each other several times a year. Tanner would let Nicholas wear his race medals; he even let his friend keep a couple of them, including one from the 113th Boston Marathon.
“John was really gentle and kind to Nicholas,” Dainiak said. “Nicholas loves the attention, loves being made to feel special, and that really made him feel special.”
The money Tanner collected was helpful, Dainiak said, but the awareness he raised has been incalculably important to the cause.
Today, Nicholas is unable to move or see. He receives nourishment through a feeding tube. Dainiak is unsure how much his son understands about Tanner’s death, but Nicholas attended the wake, wearing the two medals his benefactor had given him.
“Nicholas thought of him as a super-hero who was doing these incredible things,” Dainiak said. “He is someone who is not going to be replaced.”
Donations to the Our Promise to Nicholas Foundation can be made at www.ourpromisetonicholas.com, or by mail to PO Box 10106, Bedford, N.H. 03110.
This story originally appeared in The Boston Globe on April 4, 2013.