Orlando Sentinel -- EUSTIS -- Bored with checking IDs in Baghdad's Green Zone, Army Pfc. Derek Gibson embraced his new but vastly more dangerous assignment in Iraq, sweeping suspected hide-outs of enemy fighters.

He hunted insurgents.

"He felt he was doing what he was trained to do," Jerry Gibson, the soldier's father, said Thursday.

Army officials delivered the news Wednesday that the 20-year-old had been killed in action. Family members were told an explosive device struck a vehicle in which Derek Gibson was riding.

The U.S. Department of Defense would not confirm Gibson's death, which brings the number of Floridians killed since the start of the Iraq war to 133.

Gibson, who attended Eustis schools, enlisted in the Army about a year ago with a girlfriend. He was sent to Iraq in October.

Though surprised by their son's sudden decision, Gibson's parents encouraged him, hoping success in boot camp might boost his self-confidence.

Their son had been a mischievous youth. He dropped out of school. Once, he and neighbor Stephen Chapman, best friends since the second grade, played hooky the day after their parents met with a principal about their sons skipping school.

Tears of joy

What were you thinking? Jerry Gibson demanded of his son.

"It seemed," Derek replied, "like a good morning to go fishing."

Jerry Gibson, 54, laughed, then cried as he recounted the story: "He made you laugh so it was hard to stay mad at him."

The father also recalled a phone talk with his son Monday night after the University of Florida beat Ohio State to win the NCAA men's basketball championship.

Jerry Gibson taped the basketball game and promised to ship a copy to his son so he could lord it over a fellow soldier from Ohio. Two days earlier, the father had shipped a care package with videos, cigarettes, a battery-operated razor, socks, beef jerky and other comforts of home.

While they chatted, Jerry Gibson said he could hear explosions in the background.

Derek's mother, Janet Gibson, 50, said he spoke of the explosions around his camp as routine. He had said calmly: "I go to sleep to the thunder of mortars."

Still, his mother said, "He was reassuring to us. He didn't seem alarmed by it, so we thought he must be OK."

A dog named 'Pig'

Relatives and friends gathered at the family's modest home on Ohio Boulevard where they swapped stories of the young man who had named the family dog "Pig" and who was still searching for his place in life.

Others posted memories and condolences on his MySpace page.

His sister, Shannon, 15, was surrounded by teammates from the Eustis High School softball team. His brother, Dustin, 25, bragged about his brother's fishing prowess, showing off a photo of him holding an 8-pound bass.

His best friend's mother, Lori Chapman, compared Gibson and her son to Tom Sawyer and Huck Finn. Like Mark Twain's barefoot heroes, they were inseparable and preferred fishing to school.

"Where you found one, you usually found the other," she said. "They spent hours together and never seemed to get sick of the other."

After Gibson met a girl who talked of joining the Army, the three were supposed to sign up together. Gibson and his girlfriend enlisted, but Stephen Chapman met a girl of his own and stayed behind.

The childhood friends stayed close by e-mail and tried to talk once a week by cell phone.

Chapman, who spoke to his friend a week ago, said Gibson had recounted near misses -- dodging sniper bullets and feeling the shock of a car bomb.

"But he didn't seem frightened at all," Chapman said, his voice shaking. "He knew what happened happened for a reason."

Chapman said they were looking forward to July when Gibson was supposed to come home. They planned to hang out, laugh and fish, he said.