Michelle Miller lived by the old U.S. Army mantra: “Be all you can be.”

The 17-year-old honor student was someone “who knew she was capable of almost anything,” her grandmother, Alice Miller, told MSNBC. “This was a girl who succeeded at everything she did.” Michelle, a senior, was president of Students Against Drunk Driving. She took classes at the local college during her free time. Her older brother called her an “insanely athletic” player on the soccer and lacrosse teams, said Miller, who added that she was “fearless.” “She was always there for the other kids. Not only for the ones on top, but for the others who needed support,” she said. Michelle earned a black belt in Taekwondo before she graduated from middle school.

Michelle hoped to earn a degree in psychology at Arizona State University, with the ultimate goal of assisting struggling military personnel through the Wounded Warrior Project. She signed up to be part of the Army Reserves after a recruiter came to Rockville High School in her hometown of Rockville, Md.

Although she dressed in camouflage costumes for previous Halloween celebrations while her friends wore princess outfits, Michelle, who her grandmother said was known for her “goofy grin,” eagerly awaited the senior prom and had picked out her dress earlier this spring. “She just loved every bit of life,” Alice Miller said, “and people loved her.”

Michelle was shot and killed by a supervisor in an apparent murder-suicide on April 8. At the time, she was visiting him at his home in Germantown, Md., to try and prevent him from killing himself.

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