Alex Arrow keeps expecting to see his son, Kieran Shafritz de Zoysa, walk around the corner. He imagines his boy trailing behind him at the supermarket the way he would as a young child or playing the board games he loved or the two of them making home movies as they did earlier this month in San Diego when Kieran visited on spring break.

That he will never do those things again is like waking from a bad dream every single minute and praying it isn’t real, Arrow said in a phone interview Tuesday. Kieran, an 11-year-old who was on leave from Washington’s Sidwell Friends School and was finishing 18 months of school in Sri Lanka, was killed in one of the bombings on Easter Sunday that left 319 dead and more than 500 injured in Sri Lanka. He was supposed to return to Sidwell in the fall for sixth grade.

Arrow said Kieran was at the Cinnamon Grand Hotel in Colombo and had just sat down to brunch with his mother, Dhulsini de Zoysa of Northwest Washington, and his grandmother when the explosion tore through the restaurant. His mother and grandmother survived the attack, but Kieran was hit by three pieces of shrapnel, one of which pierced his heart, his father said.

Many time zones away, Arrow had texted with his son just minutes before the blast. The randomness of the attack has left him pondering the what-ifs.

“One of the suicide bombers got in the buffet line and apparently blew himself up in the buffet line,” he said. “If Kieran had been sitting just a foot away in either direction, it might have been totally different.”

What has been lost, Arrow said, is the life of a boy who would have done great things. He wants people to know his son was a dedicated and high-achieving student who for the last two years has wanted to be a neuroscientist and work on finding a cure for Alzheimer’s disease. Now, that future has been extinguished.

“Since he’s not going to be famous as a neuroscientist as we thought, it turns out this is what he’s going to be famous for,” Arrow said. “He only made it to age 11 1 / 2 . He’ll forever be known as the boy who was killed on Easter Sunday in the Sri Lankan bombings.”

Arrow said he wants to be sure a fuller story of his son is told.

“I just want the world to know what these particular terrorists took from the world,” he said. “In addition to being a neuroscientist, which we knew he was going to be, he was at the top of his class at Sidwell. And at his school in Sri Lanka, he had an A double star average and was the only one in his school that had that. He was very determined, and he was going to achieve his goals.”

Arrow, a doctor who heads a medical device start-up company, remembered taking Kieran on a trip during vacation. His son insisted that part of each day be spent studying Mandarin, a language he wanted to speak fluently. He was also learning Sinhala, one of Sri Lanka’s official languages.

As Arrow pondered the future his son will never have, he consoled himself with a flood of memories. The funny shapes they made with pancakes. The camping trips. The Halloween costumes. The sweet smile on Kieran’s face in every photograph.

When Kieran visited in April, they went kayaking in Lake San Vicente in Lakeside, Calif.

“He really got into that,” Arrow said. “And it’s a good opportunity to have the deep father-son discussions when the two of you are out in kayaks in the middle of a big body of water. It was kayaking, but it was really just a way to talk.”

Kieran would have turned 12 in August. More than anything, his father wants people to know his goodness and his heart.

“He was totally altruistic. He did everything he did because he wanted to help people,” Arrow said. “And that’s who the terrorists took away from us. . . . If they were trying to do the maximum damage, they don’t know how well they succeeded.”