Watertown’s John Airasian will run the Boston Marathon this year, his first full marathon, to raise money for Boston Children’s Hospital. A Watertown man has decided to run the Boston Marathon for the first time to raise money for the hospital that cared for his young son when he needed surgery. John Airasian has pledged to raise $10,000 for Boston Children’s Hospital, and hopes to surpass that amount. He wants to help the people who helped his son. “A few years back, my son Michael was admitted into Children’s Hospital to have an internal cyst removed from his throat and I was able to witness the care that all the Doctor’s, Nurses and Staff at BCH give,” Airasian said.