“He really used it to express himself and his emotions,” DeMarco said of Battiste’s love for the guitar, adding that Battiste—who had stayed with DeMarco for a few months in the past year—would wake up and play throughout the day until 2 a.m.

Adding to his list of accomplishments, Battiste was on the Board of Directors of SolSolution, a non-profit organization that seeks to generate sustainable solutions for renewable energy. Battiste organized the capital accumulation campaign and contributed to the group’s strategic planning as a volunteer, according to the organization’s website.

“Brien was so inspiring to me and really passionate about making our world better,” said Soren D. Harrison, founder and chief executive officer of SolSolution. Battiste worked for the organization for more than a year during his time at Harvard, but dropped off in his involvement in 2009.

“No matter what life throws at you, you can achieve really great success,” Harrison said, recalling the day that Battiste learned he had gotten accepted into Harvard, his dream school. “That’s what’s so disappointing and [why I’m] angry about his death is that he didn’t really get to achieve what he wanted to.”

“It’s hard to relate how deeply I miss Brien and what a huge hole he’s left in a lot of people’s lives,” Gromek wrote. “For me in particular, it was like losing a brother.”

—Staff writer Xi Yu can be reached at xyu@college.harvard.edu.