Kaiser was the bat boy for the Bee Jays, a summer league team for college baseball players. Bee Jays pitcher Kadon Simmons told the Kansas City Star the boy was a “spark plug” for the team.

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The report also noted the closeness between Kaiser and Keirsie.

“They’d walk home to their grandparents’ house from school together,” school counselor Cathi Crosier told the Star. “Kaiser looked out for her every day. If she was upset about something, he’d comfort her. He was very protective of his little sister.”