The boy is a kindergarten student at Cimarron Elementary School in Katy ISD. He has not been identified. According to a letter from the principal sent home to Cimarron parents, one of the students was injured while watching the race.
We're told his injuries were not life-threatening and he is expected to make a full recovery.
The message also reminded worried moms and dads to talk to their kids, who might be worried about their classmates.
"I was surprised someone so close to home that was there. I was concerned about her thinking, 'Oh my gosh, I wonder if it's one of her classmates,'" concerned parent Kimberly Bouchard said.
Meanwhile, in Medford, Massachusetts, a vigil was held Wednesday night to remember the life of 29-year-old Krystle Campbell.
Hundreds gathered Tuesday night to honor the youngest of those killed: 8-year-old Martin Richard.
And on the campus of Boston University, students were mourning over Lingzi Lu, 23, who lost her life in the bombings.
Stay with Eyewitness News and abc13.com for the latest on this story.
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