Alan and Lavonne Smith raised their son, Derek, to serve family, country and the Florida Gators.

"One year he was in Iraq for 15 months," Lavonne says. "And instead of Christmas, Thanksgiving or some other time you would think he would come home, he came home for the Florida-Georgia game and the party."

Derek graduated from University Christian in Jacksonville back in 2002.

"His favorite picture show was Saving Private Ryan," his dad says.

Five years later, he joined the United States Army.

Derek served in Iraq and rose to the rank of Sergeant. He was stationed at Fort Belvoir in Virginia as a military police officer.

"All he wanted was to be a policeman," Lavonne says. "So we had to buy (toy) police cars everywhere we went."

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He was a decorated soldier as well. But his mom says he never bragged about himself or desire to be the center of attention. He was easygoing, according to Lavonne. But Derek never told his parents much about his life in the army.

"He told me one time and I don't think he meant to tell me," Alan says. "He says, 'Dad, you know I'm in the first squad... you know what that means,' and I said no... he says, 'We're the first ones out on the convoy.'"

Both mom and dad spoke with their son on the phone often but there's one conversation they'll never forget.

"I talked with him just briefly that day," Lavonne says, "thinking I'll talk to him tomorrow."

That was Aug. 19, 2012. While out on duty that night, Derek shot himself in the head. He didn't leave a note. Didn't say why.

"Everyday I look up to heaven and say, 'Derek, why did you do that? You had everything going on. I just can't think of any reason why you would do that,'" Alan says. "He bought a set of tires the day before and if you were thinking about committing suicide, you wouldn't buy a set of tires for your car."

But there was something said during that last call to his parents -

"I asked him is there was anything new, if everything was alright," Lavonne explains. "It was a brief conversation because he called frequently, he said, 'no, mom. Everything's great. Everything's fine.'"

"All of the soldiers," Alan says, "several of them came down here when we had the funeral - nobody had no inclination whatsoever."

The family had close friends whose daughter committed suicide 5 years before Derek killed himself.

"The night I learned of that... I called them and the very first thing they told me - that I won't forget," Alan says, "is that it's not your fault. Because you fell like... what could I have done... what did I not do... that caused Derek to take his life - and my friend said it's not your fault. Always remember that."

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